PLEASE HELP I ONLY HAVE 3 MINUTES NOW 1. Find f(3).

f(x) = x^2 + 5x - 9
A) 7
B) 10
C) 9
D) 15

2.
If f(x) = -x^3 + 2x^2- 3, find f(2).
A) -19
B) -3
C) -1
D) 5

1. D) 15

2. B) -3

Step-by-step explanation:

I can't provide you with the step by step explanation within 3 minutes but I guarantee you that these are the right answers.

1 = 15

2 = -3

Step-by-step explanation:

I used my scientific calculator for answers

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12

the answer to the expression is 83