Factoring
Limits
Horizontal Asymptotes
End Behavior
Domain
100

Factor  f(x)=x^2+22x+7 .

Multiply: 21; Add: 22  ->  1 and 21

 f(x)=3x^2+21x+1x+7 

f(x)=3x(x+21) + 1(x+7)

f(x)=(3x+1)(x+7)


100

How would you read lim_(x->3^+)f(x) ?

What is the limit of f(x) as x approaches 3 from the right?

100

Does r(m) = (3m^3+6m-4)/(5m^5-2) have a horizontal asymptote? If so, where is it?

Degree of denominator > Degree of numerator

There is a horizontal asymptote at r(m) = 0

100

Find the end behavior of  f(x)=-3x^5+6x^2+2.

Leading term:  -3x^5 

lim_(x->infty)f(x)=-infty 

lim_(x->-infty)f(x)=infty

100

State the domain of  f(x)=(2x^2-7x-15)/((x-7)(x+4)(x-2)) 

 (-infty, -4) cup(-4,2) cup(2,7) cup (7,infty) 

200

Factor  g(x) = 5x^2-21x+22 .

Multiply:  5*22=110 , Add to -21 -> -10, -11 .

 5x^2-10x-11x+22 

5x(x-2)-11(x-2)

(5x-11)(x-2)

200

Find  lim_(x->-1^-)g(x) 

lim_(x->-1^-)g(x)=1

200

Does  g(x)= (4x^2+9x+2)/(3x+6) have a horizontal asymptote? If so, where is it?

Degree of numerator > Degree of denominator.

There is no horizontal asymptote.

200

Find the end behavior of  g(x)=3x^2(-2x+4)^3(x-3)^5 

Leading term:   (3x^2)(-2x)^3(x^5)=3x^2(-8x^3)(x^5)=-24x^10 

 lim_(x->infty)g(x)=- infty 

 lim_(x->-infty)g(x)=-infty 

200

State the domain of  (4x^5+3x^3+9x-13)/(x^2(x+3)(x-1) 

 (-infty,-3)cup (-3,0)cup(0,1)cup(1,infty) 

300

Factor  a(b) = 3b^3-7b^2-6b .

Factor out b:  b(3b^2-7b-6) .

Multiply to: 3(-6) = -18, Add to -7  -> -9, 2 .

b(3b^2-9b+2b-6)

b(3b(b-3)+2(b-3))

b(3b+2)(b-3)

300

Find lim_(x->5^+)g(x) 

lim_(x->5^+)g(x)=2

300

Does  f(x)= (6x^3+8x^2+2)/(3x^3+9x+9) have a horizontal asymptote? If so, where is it?

Degree of numerator = Degree of denominator

Horizontal asymptote at   f(x)=6/3=2 

300

Find the end behavior of  f(x)=(2x^4+6x-2)/(3x^5-2x^4+6x^2+19) 

Degree of numerator < Degree of denominator

Horizontal asymptote at f(x)=0

 lim_(x->infty)f(x)=0 

 lim_(x->-infty)f(x)=0

300

State the domain of  ((x+6)(4x-16))/((2x+3)(x-19)) 

 2x+3 = 0 -> 2x = -3 ->x=-3/2 

Domain:  (-infty,-1.5)cup(-1.5,19)cup(19,infty) 

400

Factor  r(x) = 2x^4+4x^3-16x^2. 

Factor out  2x^2 -> r(x) = 2x^2(x^2+2x-8) 

Multiply to:  1*(-8)=-8 , Add to: 2  -> 4, -2 .

2x^2(x^2+4x-2x-8)

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

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

400

Find  lim_(x->1^+)f(x) 

lim_(x->1^+)f(x)= infty 

400

Does  g(x)= ((x+2)^3(2x-1))/((x-2)^2(3x+1)^2) have a horizontal asymptote? If so, where is it?

Leading term of N(x) =  (x^3)(2x) = 2x^4 

Leading term of D(x) =  (x^2)(3x)^2=x^2(9x^2)=9x^4 

Degree of numerator = Degree of denominator

Horizontal asymptote at g(x) = 2/9  


400

Find the end behavior of  f(x)=(8x^4+9x^2-42)/(-2x^4+12x^3+82x) 

Degree of numerator = Degree of denominator

Horizontal asymptote at y= 8/(-2)=-4

lim_(x->infty)f(x)=-4 
lim_(x->-infty)f(x)=-4 

400

State the domain of   (6x^2+18)/(2x^5-7x^4-15x^3) 

Factor the denominator, factor out: x^3 , Multiply to -30, Add to -7 ->  -10 and 3

 x^3(2x^2-10x+3x-15)  

 x^3(2x(x-5)+3(x-5))  

 x^3(2x+3)(x-5)  

 2x+3 = 0 -> 2x=-3 -> x=-1.5  

Domain: (-infty,-1.5)cup(-1.5,0)cup(0,5)cup(5,infty) 

500

Factor  k(x) = -3x^2+3x+6 .

Factor out  -3 -> k(x)= -3(x^2-1x-2) .

Multiply to:  1*(-2)=-2 , Add to:  -1-> -2, 1

k(x)=-3(x^2-2x+1x-2)

k(x)=-3(x(x-2)+1(x-2))

k(x)=-3(x-2)(x+1)

500

Find  lim_(x->3^+)f(x) and  lim_(x->3^-)f(x). 

lim_(x->3^+)f(x)=-3

 lim_(x->3^-)f(x)=1.5 

500

Does  h(x)= ((-x+2)^5(-6x-1)^2)/((x+8)^6(3x^2+4)^2) have a horizontal asymptote? If so, where is it?

Numerator leading term:  (-x)^5(-6x)^2 = -x^5(36x^2)=-36x^7 

Denominator leading term:  x^6(3x^2)^2=x^6(9x^4)=9x^10 

Degree of denominator > Degree of numerator

Horizontal asymptote at h(x) = 0

500

Find the end behavior of  (15x^7+19x^6+3x^5-2x^4-84x^2)/(-3x^3+7x+10).

Degree of numerator > Degree of denominator (15x^7)/(-3x^3)=-5x^4

lim_(x->infty)f(x)=-infty

lim_(x->-infty)f(x)=-infty 

500

State the domain of  (2x^2-7x+5)/(3x^2-10x+8) 

Factor the denominator: 

 Multiply to 24, Add to -10  -> -6 and -4

 3x^2-6x-4x+8 

 3x(x-2)-4(x-2) 

 (3x-4)(x-2) 

 3x-4=0->3x=4 ->x=4/3 

Domain:  (-infty,4/3)cup(4/3,2)cup(2,infty)