MTH 121 Exam 3 Review

Simplifying Rational Expressions

100

Find the Domain of 

(4x+2)/(x^2-25)

WRITE IN INTERVAL NOTATION

(-oo,-5)U(-5,5)U(5,oo)

200

Simplify the Rational Function: 

(x-8)/(x^2-3x-40)

1/(x+5)

300

Perform the indicated operation: 

x/(7x-28)*(x^2-4x)/4

x^2/28

400

Perform the indicated operation:

(x^2+12x+20)/(x^2-4x-12)/(x^2+20x+100)/(x^2-x-30)

(x+5)/(x+10)

Solving Rational Equations

100

Perform the indicated operation:

4/x+7/(2x^2)

(8x+7)/(2x^2)

200

Perform the indicated operation:

(3x)/(x^2-16)-(7)/(x+4)

-(4x-28)/((x+4)(x-4))

300

Solve & Check:

x/(x-7)=(-5)/(x-3)

x=5,-7

400

Solve & Check:

1/(x+9)+18/(x^2-81)=1

x=10

Complex Fractions & Equations

100

If y varies directly as x, find the constant of variation k, when x = 28 and y = 56.

k=2

200

Simplify the Complex Fraction:

(11/(3x))/(3/(4x))

44/9

300

If y varies directly as

x^2

 and y = 100 when x = 5, find the constant k. Then find y when x = 3. (Write what K equals and what y equals)

k=4

y=36

400

Simplify the complex fraction:

(3x^-1+5y^-2)/(x^-1-y^-1)

(3y^2+5x)/(y^2-xy)

OR

(3y^2+5x)/(y(y-x))

Simplifying Radicals

100

Simplify:

sqrt(25x^6)

5x^3

200

Simplify:

sqrt(30)

sqrt(30)

300

Simplify:

sqrt(48x^10y5)

4x^5y^2sqrt(3y)

400

Simplify:

2(2sqrt(5x^3)+5xsqrt(20x))

24xsqrt(5x)

Formulas

100

Find the formula for

(1/a)/(1/b)

1/a*b/1=b/a

200

How would a square root be written as a power?

sqrtx=x^(1/2)

300

Find the formula for:

n_sqrt(ab)

n_sqrta*n_sqrtb

400

(Without looking at your notes)

What is the distance formula?

sqrt((x_2-x_1)^2+(y_2-y_1)^2)

Reviewing Past Topics

100

Factor:

x^2-16

(x+4)(x-4)

200

Find the slope of the line passing through the points (2,3) and (4,7).

m=2

300

Multiply:

(2x+5)(2x^2-x+2)

4x^3+8x^2-x+10

400

Simplify:

(2a^2*2b^3)^3/(4a*b^2)^2

4a^4b^5