Integration question (quick 10 points will vote asap)

Integrate dx/(1+(8x+9)^2)

The answer im getting is 8tan^-1(8x+9) + C but its not on the multiple choice selection

or at least i dont think

a) 1/8 tan^-1 (x+9) + c - i think its this one but i cant see it
b) 1/8 tan^-1 (8x+9) + c
c) tan^-1 (8x+9) + c

Let us take (8x + 9) = t
=> 8dx = dt
dx = dt/8

Now substituting with t and dt

1/8 dt/(1 + t^2)
1/8 tan^-1 t + C
Now re substituting t

ANSWER: 1/8 tan^-1 (8x + 9) + C
(B)

Integration by substitution is not required for this problem, just integrate as normal then divide by the derivative of the bracket instead of multiplying by it.

∫ 1 / [1 + (8x + 9)²] = tanˉ¹(8x + 9) / 8 + C

The answer shud be (b) if u subtitute well