Real numbers and graphs

Question 1

What is absolute value?

Answer 1

[a]= (a a> 0, -a a<0)
[-2]=2

Question 2

Are square roots always positive?

Answer 2

Yes

Question 3

What is an open interval

Answer 3

a<x<b

Question 4

What is a closed interval

Answer 4

a <= x <= b

Question 5

What is the distance formula?

Answer 5

square root of [(x1-x2)^2 +(y1-y2)^2]

Question 6

What is the formula of a circle?

Answer 6

(x-x0)^2+(y-y0)^2=R^2
(x0,y0) is the midpoint of the circle

Question 7

What are functions

Answer 7

one x can only have one y

Question 8

How do you know if a function is increasing?

Answer 8

If f(x) < f(x2) if x1< x2

Question 9

How do you know if a function is decreasing?

Answer 9

If f(x) > f(x2) if x1<x2

Question 10

How do you know if a function is odd?

Answer 10

x^3, x^5
f(-x)= -f(x)

Question 11

How do you know if a function is even?

Answer 11

x^2, x^4
f(-x)=f(x)

Question 12

What is a quadratic?

Answer 12

y=ax^2+bx+c

Question 13

How do you find the roots of quadratic?

Answer 13

factor, complete the square

Question 14

What is the quadratic formula?

Answer 14

x= -b+ or - square root (b^2-4ac) divided by 2a