# Calc

posted by .

Find f'(a).

f(x)= (x^2 + 1)/(x - 2)

So,

[[(a + h)^2 + 1]/[(a + h) - 2]] - [(a^2 + 1)/a - 2] and the whole thing divided by h

I tried simplifying it and ended up with [a + h/-2] - (a-2), which is incorrect. I used wolfram alpha and got (a^2 - 4a - 1)/(a - 2)^2 but I do not know how to get this. Please help.

• Calc -

numerator
(a^2+2ah+h^2+1)(a-2) -(a^2+1)(a+h-2)

a^3+2a^2h+ah^2+a-2a^2-4ah-2h^2-2 -a^3-a-a^2h-h+2a^2+2

that is
a^2h + ah^2 -4ah -h

divide numerator by h
a^2 +ah -4a -1
let h-->0
a^2-4a-1 sure enough now denominator
(a-2)(a+h-2)
let h-->0
(a-2)^2 sure enough

## Similar Questions

1. ### math

Please can you help me with the following two questions?
2. ### physics

I'm confused as how to find the current for a circuit with both parallel and series resistors?
3. ### Calculus

Find f'(a). f(x)= (x^2 + 1)/(x - 2) So, [[(a + h)^2 + 1]/[(a + h) - 2]] - [(a^2 + 1)/a - 2] and the whole thing divided by h I tried simplifying it and ended up with [a + h/-2] - (a-2), which is incorrect. I used wolfram alpha and …

5. ### Algebra

"Find the maximum value of y/x over all real numbers x and y that satisfy (x - 3)^2 + (y - 3)^2 = 6." I tried simplifying it to xy(x+y-12), went nowhere.
6. ### Estimation decimal quotient

Use compatible numbers to find the each quotient ,2.90 divided by 29,48 divided by 3.2, 0.18 divided by 0.33,152 divided by 5.12,41.9 divided by 19,33.90 divided by 10.2, 502 divided by 9.5, 180.8 divided by 6 , 48 divided by 3.33, …
7. ### Algebra

Given the function f(x)=3x^3+2, find the value of x so that f^-1(x)=4. Thank you. I tried to solve for the inverse by susbsituting y in for x so: x=3y^3+2 and then I subtracted 2 so x-2=3y^3 and I am stuck here, do I just cube root …
8. ### Geometry / Math

Hi guys I need help ASAP, I have tried every thing I know about math and I cant figure any of them out. Thank you... _________________________________ 1. Use a formula to find the surface area of the square pyramid. (H.6ft.)(W.3ft.)(L.3ft.) …
9. ### MATH

Hi guys I need help ASAP, I have tried every thing I know about math and I cant figure any of them out. Thank you... _________________________________ 1. Use a formula to find the surface area of the square pyramid. (H.6ft.)(W.3ft.)(L.3ft.) …
10. ### Pre-Algebra

A fair number cube, numbered 1 though 6 is rolled 200 times. About how many times can it be expected to on the number 4?

More Similar Questions