Question

i'm so confuse with this problem I have to use the limits rules but find the derivative B. F (x)= x²-16/x-4=?

Answer 1

hmm, well, that's an easy one :/

Answer 2

notice \(\bf x^2-16\\
\text{keep in mind that}\\
(a-b)(a+b) = (a^2-b^2)
\)

Answer 3

-15?

Answer 4

i think i have to subtract but i don't really remember the derivative rules :s

Answer 5

well, you want the derivative of f(x) right?

Answer 6

yes

Answer 7

so \(\bf \cfrac{x^2-16}{x-4}\\
\cfrac{x^2-4^2}{x-4} \implies \cfrac{\cancel{(x-4)}(x+4)}{\cancel{x-4}}\\
x+4\)

Answer 8

from there just use the power rule to get the derivative of x+4

Answer 9

O_o wow lol u made it look so easy.... hehehe thanks

Answer 10

yw

Answer 11

so using the power rule, derivative of \(\bf x^{1}\) is 1, and 4 is a constant so derivative of a constant is 0, so
1 + 0 => 1

Answer 12

-_- goodness I found this site (y) @jdoe0001