Mathematics Dictionary
Dr. K. G. Shih
Graphic Solutions
Questions
Symbol Defintion
Example : Sqr(x) = Square root of x
AL 21 00 |
- How to use sketch program ?
AL 21 01 |
- Polynomial Functions
AL 21 02 |
- Functions in factor forms
AL 21 03 |
- Rational functions
AL 21 04 |
- Exponent and logarithm
AL 21 05 |
- Functions with absolute operation
AL 21 06 |
- Functions and its inverse
AL 21 07 |
- Intersections of quadratic functions with other functions
AL 21 08 |
- Solve x^7 + 2*x^6 - 5*x^5 - 13*x^4 - 13*x^3 - 5*x^2 + 2*x + 1 = 0
AL 21 09 |
- Diagram of y = (x-1)*(x-2)*(x-3)
AL 21 10 |
- Diagram of y = x + 1/x
AL 21 11 |
- Diagram of y = x^2 + 1/x
AL 21 12 |
- Diagram of y = x^3 + 1/x
AL 21 13 |
- Diagram of y = (x^3)/(x^2 - 1)
AL 21 14 |
- Diagram of y = (x^4)/(x^2 - 1)
AL 21 15 |
- Diagram of e^x + e^(2*x) + e^y + e^(2*y) = 12
AL 21 16 |
- Diagram of y = x^2 - 6*x + 8 and its inverse
AL 21 17 |
- Diagram of y = Abs(x^2 - 6*Abs(x) + 8)
AL 21 18 |
- Examples
Answers
AL 21 01. Polynomial Functions and equations
Diagram program
Sketh Programs |
Find graphic solutions.
Functions
01 01 y = a*x + b
01 02 y = a*x^2 + b*x + c
01 03 y = a*x^3 + b*x^2 + c*x + d
01 04 y = a*x^4 + b*x^3 + c*x^2 + d*x + e
01 05 y = a*x^5 + b*x^4 + c*x^3 + d*x^2 + e*x + f
Example : Sketch y = x^2 - 6*x + 8
Start sketch programs
Click Menu command
Click polynomial functions in upper box
Click y = a*x^2 + b*x + c in lower box
Give coeffcient a, b, c : 1, -6, 8
Demo examples
01 11 Function highest Power is 7
01 13 Quartic equation
01 14 Quartic equation
01 45 Find F(u+v*i) of example 01 11
Go to Begin
Q02. Functions in factor forms
Diagram Programs
Sketh Programs |
Find graphic solutions.
Functions
02 06 y = (x-a)*(x-b)*(x-c)*(x-d) - e
02 38 y = (x-a)*(x-b)*(x-c)
02 39 y = (x-a)*(x-b)*(x-c)*(x-d)
02 40 y = (x-a)*(x-b)*(x-c)*(x-d)*(x-e)
02 41 y = (x-a)*(x-b)*(x-c)*(x-d) and y = e
02 40 y = (x-a)*(x-b)*(x-c)*(x-d)*(x-e) and y = f
Example : Find the domain of y = (x-1)*(x-2)*(x-3) when y is postive
Start sketch programs
Click Menu command
Click Section 2 of functions in factor form in upper box
Click program 38 y = (x-a)*(x-b)*(x-c) in lower box
Give constants a, b, c : 1, 2, 3
Demo examples
02 09 Function highest Power is 7
02 10 Quartic equation
02 12 Quartic equation
Go to Begin
Q03. Rational functions
Diagram Programs
Sketh Programs |
Find graphic solutions.
Functions
03 07 y = 1/(a^x^2 + b*x + c)
03 08 y = 1/(a^x^3 + b*x^2 + c*x + d)
03 24 y = 1/x
03 30 y = ((x-1)^M)/(2*x)
03 31 y = ((x-1)^M)/(2*x)
03 47 y = x + 4/(x^2)
Example : Find the asymptotes y = ((x-1)^3)/(2*x)
Start sketch programs
Click Menu command
Click Section 3 of functions in rational function in upper box
Click program 30 y = ((x-1)^3)/(2*x) in lower box
Give power M as 3
Demo examples : Find asymptotes
03 24 y = 1/x
03 47 y = x + 4/x^2
Sketch y = (a*x^3 + b*x^2 + c*x + d)/(p*x^3 + q*x^2 + r*x + s)
See rational function in graphic calculator : GC 03 10
GC
Graphic Calculator : Y = F(x)
Example : Sketch y = x + 1/x
Let y = (x^2 + 1)/x
Use GC 03 08
Give coeffcients : 0,1,0,1 0,0,1,0
From graph we see that asymptotes : x = 0 and y = x.
Go to Begin
Q04. Exponent and logarithm
Diagram Program
Sketh Programs |
Find graphic solutions.
Functions
04 15 y = sinh(x)
04 16 y = cosh(x)
04 17 y = tanh(x)
04 18 y = csch(x)
04 19 y = sech(x)
04 20 y = coth(x)
04 21 y = exp(x)
04 22 y = exp(-x)
04 23 y = ln(x) or log(x) base e
04 33 y = exp(x) and y = ln(x)
04 34 y = exp(x) and y = exp(-x)
04 44 Equation : e^x + e^(2*x) + e^y + e^(2*y) = 12
Example : Find the asymptotes of e^x + e^(2*x) + e^y + e^(2*y) = 12
Start sketch programs
Click Menu command
Click Section 4 of exponent and logarithm in upper box
Click program 44 in lower box
No data is required. Find asymptote from diagram.
Reference : See Exponent in Algebra
Demo examples
All programs are demo
Study example using 04 33
1. Find intersections of y=exp(x) with its inverse
2. Find intersections of y=ln(x) with its inverse
Compare y = sinh(x) and y = sin(x)
See PM 14 00
Go to Begin
Q05. Functions with absolute operation
Diagram program
Sketh Programs |
Find graphic solutions.
Functions
05 25 y = Abs(a*x + b)
05 26 y = a*Abs(x) + b
05 27 y = a*x^2 + b*Abs(x) + c
05 28 y = Abs(a*x^2 + b*x + c)
05 29 y = Abs(a*x^2 + b*Abs(x) + c)
05 46 Solve Abs(a*x^2 + b*Abs(x) + c) = d
Example : How many real roots in Abs(x^2 - 6*Abs(x) + 8) = 0.5
Start sketch programs
Click Menu command
Click Section 5 in upper box
Click program 46 in lower box
Give data a, b, c, d : 1, -6, 8, 0.5
Reference : See Inverse in Algebra
Demo examples
Click Menu and then click Demo
Select section 5
Select program
Go to Begin
Q06. Functions and its invsers
Diagram program
Sketh Programs |
Find graphic solutions.
Functions
06 32 y = a*x + b
06 33 y = a*x^2 + b*x + c
06 35 y = exp(x)
06 35 y = ln(x)
Example : How many intersections of y = a*x^2 + b*x + c with its inverse
GC |
Graphic Calculator : y = F(x).
Example 1 : None. See GC 06 01
Example 2 : One.. See GC 06 02
Example 3 : Two.. See GC 06 03
Example 2 : four. See GC 06 04
Example : Find intersections of y = x^2 - 6*x + 8 with its inverse from graph
Sketch program in GC 06 10
Go to Begin
Q07. Intersections of quadratic functions with other functions
Diagram program
Sketh Programs |
Find graphic solutions.
Functions
07 36 with y = 1/x
07 37 with y = p*x + q
Example : How many intersections of y = a*x^2 + b*x + c with y = 1/x
GC |
Graphic Calculator : y = F(x).
Example 1 : Two.... See GC 06 07
Example 2 : One.... See GC 06 08
Example 3 : Three.. See GC 06 09
Example : Find intersections of y = x^2 - 6*x + 8 with y = 1/x from graph
Sketch program in GC 06 11
Example : Find intersections of y = x^2 - 6*x + 8 with y = x - 2 from graph
Sketch program in GC 06 12
Go to Begin
Q08. Solve x^7+ 2*x^6- 5*x^5- 13*x^4- 13*x^3- 5*x^2+ 2*x+ 1 = 0
Method
Equation |
Mehtods
Diagram
Find solution using diagram
1. Estimate the real roots
2. Find the complex roots if we know real roots
Go to Begin
Q09. Diagram of y = (x-1)*(x-2)*(x-3)
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
Diagram
Go to Begin
Q10. Diagram of y = x + 1/x
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
4. Find equations of asymptotes
Diagram
Go to Begin
Q11. Diagram of y = x^2 + 1/x
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
4. Find equations of asymptotes
Diagram
Go to Begin
Q12. Diagram of y = x^3 + 1/x
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
4. Find equations of asymptotes
Diagram
Go to Begin
Q13. Diagram of y = (x^3)/(x^2 - 1)
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
4. Find equations of asymptotes
Diagram
Exercise : Sketch y = (x^3)/(x^2 - 1)
Graphic Calculator |
Section 3 and program 08.
Note : Data are 1,0,0,0,0,1,0,-1
Go to Begin
Q14. Diagram of y = (x^4)/(x^2 - 1)
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
4. Find equations of asymptotes
Diagram
Go to Begin
Q15. Diagram of e^x + e^(2*x) + e^y + e^(2*y) = 12
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
4. Find equations of asymptotes
Diagram
Go to Begin
Q16. Diagram of y = x^2 - 6*x + 8 and its inverse
Questions : Using the diagrams
1. Find domains if y is positive
2. Find domains if the curve is increasing
3. Find domains if the curve has maximum or minimum points
4. Find equations of asymptotes
Diagram
Go to Begin
Q17. Diagram of y = Abs(x^2 - 6*Abs(x) + 8)
Questions : Using the diagrams
1. Solve Abs(x^2 - 6*Abs(x) + 8) = 0.5
2. Solve Abs(x^2 - 6*Abs(x) + 8) = 1.0
Diagram
Go to Begin
Q18. Examples
Study notes of y = a*x^3 + b*x^2 + c*x + d
1. Cubic functions : Highest power is 3.
2. Slope of cubic function is y' = 3*a*x^2 + 2*b*x + c (a parabola).
Curve is increasing if y' is positive.
Curve is decreasing if y' is negative.
Curve has critical point if y' = 0
3. Vertex
It has none vetex.
It has two vetices.
4. Concavity
Concave upward upward if 2nd derivative is positive.
Concave upward downward if 2nd derivative is negative.
Point of inflexion if 2nd derivative is zero.
5. Zero values of y
It has 3 zeros.
It has 2 zeros (One duplicate real roots)
It has 1 zero. (Two complex roots)
6. Cubic formula : It is used in MD2002 Lesson 17.
7. Example
What is the expression of the demo function ?
Polynomila form
Factor form
What is the y-intercept ?
what are the zero values of y ?
What are the coordinates of the critical points ?
What is the domian for y on graph when y is less than zero ?
7. Exercises
1. Sketch y = x^3
2. Sketch y = x^3 -2*x^2 - x + 2
Study notes of y = a*x^4 + b*x^3 + c*x^2 + d*x + e
1. Slope of cubic function is y' = 4*a*x^3 + 3*b*x2 + c*x + d.
Curve is increasing if y' is positive.
Curve is decreasing if y' is negative.
Curve has critical point if y' = 0
3. Vertex
It has one or three vetices.
4. Concavity
Concave upward upward if 2nd derivative is positive.
Concave upward downward if 2nd derivative is negative.
Point of inflexion if 2nd derivative is zero.
5. Zeros of y
It has no zero of y. (Four complex roots).
It has one zero of y. (One duplicate real and two complex).
It has three zeros of y. (One duplicate real and two different real)
It has four zeros of y. (Four different real roots)
6. Quartic formula :
It used to find four complex roots
It is used in MD2002 Lesson 17.
Study the graph of demo question in Program 04
What is the expression of the demo function ?
Polynomila form
Factor form
What is the y-intercept ?
what are the zero values of y ?
What are the coordinates of the critical points ?
What is the domian for y on graph when y is less than zero ?
Exercises
1. Sketch y = x^4 + 4*x^3 + 6*x^2 + 4*x + 1
2. Sketch y = x^4 - 4*x^3 - x^2 + 16*x - 12
Study notes of y = a*x^5 + b*x^4 + c*x^3 + d*x^2 + e*x + f
1. Slope of quaint function is y' = 5*a*x^4 + 4*b*x3 + 3c*x^2 + 2*d*x + e.
Curve is increasing if y' is positive.
Curve is decreasing if y' is negative.
Curve has critical point if y' = 0
3. Vertex
It has none, two or four vetices.
4. Concavity
Concave upward upward if 2nd derivative is positive.
Concave upward downward if 2nd derivative is negative.
Point of inflexion if 2nd derivative is zero.
5. Zeros of y
It has one zero of y. (One real root and Four complex roots).
It has two zeros of y. (One real, One duplicate real and two complex).
It has three zeros of y. (One duplicate real and one different real)
It has four zeros of y. (Three different real and one duplicate)
It has five zeros of y. (Five different real)
6. Quaint formula : It may not be availble in mathematic field.
7. Study the graph of demo question in Program 01 05
What is the y-intercept ?
what are the zero values of y ?
What are the coordinates of the critical points ?
What is the domian for y on graph when y is less than zero ?
8. Exercises
1. Change y = x^5 - 8*x^4 + 15*x^3 + 20*x^2 - 76*x + 48 to factor production
2. Above function have roots p,q,r,s,t. Find p*q*r*s*t (Production)
2. Above function have roots p,q,r,s,t. Find p+q+r+s+t (Sum)
Go to Begin
Q00. How to use sketch program
Sketh Programs |
Find graphic solutions.
1. Start sketch program
Clcik sketch program
Select run at current location
Select yes to run
2. Sketch y = x^2 - 6*x + 8 which is in 01 02
Click Menu command
Click polynomial function in section 1 in upper box
Click Program 02 in lowe box
Give coefficients a, b, c : That is 1, -6, 8
3. How change scale and replot ?
After we get the graph, we select new xmax and ymax in left box
Click replot
4. What is demo command ?
Click Menu then click Demo
Select a section number
Slect a program
It will give a plot using default values.
For example : What is the function of 01 04 ?
5. What is the meaning of 01 04 ?
First number is the section number in upper box
Second number is the function number in lower box
Factor form : y = (x-a)*(x-b)*(x-c) in Program 38
1. Change to polynomial using program 38.
2. Method 2 : Use multiplication of polynomials.
3. Find y-intercept.
4. Quick sketch : Use 3 zeros and y-intercept to plot the curve.
Factor form : y = (x-a)*(x-b)*(x-c)*(x-d) in Program 39
1. Change to polynomial using program 39.
2. Method 2 : Use multiplication of polynomials.
3. Find y-intercept.
4. Quick sketch : Use 4 zeros and y-intercept to plot the curve.
Factor form : y = (x-a)*(x-b)*(x-c)*(x-d)*(x-e) in Program 40
1. Change to polynomial using program 40.
2. Method 2 : Use multiplication of polynomials.
3. Find y-intercept.
4. Quick sketch : Use 5 zeros and y-intercept to plot the curve.
Solve (x-a)*(x-b)*(x-c)*(x-d) = e
Study Program |
Graphic Solutions of Polynomial Functions.
Graphic method 1 : Sketch y = (x-a)*(x-b)*(x-c)*(x-d) - e
Zeros of y are the solution (Program 06)
What is the question ? What are the solutions
Graphic method 2 : Sketch y = (x-a)*(x-b)*(x-c)*(x-d) and y = e
Intersections of line and curve the solution (Program ??)
What is the demo question ? What are the solutions ?
Examples
Program 09 : y = (x-5)*(x-7)*(x+4)*(x+6) - 504
Program 10 : y = (x+9)*(x-3)*(x-7)*(x+5) - 385
Program 12 : y = (28x-7)*(x-3)*(x+3)*(2*x+5) -91
Program 13 : y = 12*x^4 - 56*x^3 +59*x^2 - 56*x + 12
Program 14 : y = x^4 + x^3 - 4*x^2 + x + 1
Go to Begin
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