What is the sum?
3/x^2-9 + 5/x+3
a) 8/x^2+x-6
b) 5x-12/x-3
c)-5x/(x+3(x-3)
d) 5x-12/x+3(x-3)

Sum  

D is correct

Step-by-step explanation:

Given:

We are given a rational expression and to add the expression.

First we make common denominator and then we add them

Multiply and divide the second fraction  by x-3

Now we have common denominator and write as common

Factor the denominator:

Hence, The sum  is  

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

560

step-by-step explanation:

giggidy