tolong dijawab pake cara ya makasih

Integral dgn substitusi
₁∫⁵ (2x)/(x² +1)² dx=
..
u = x² + 1 --> du = 2x dx 
x = 1 --> u = 1²+1 = 2
x = 5 --> u = 5² + 1 = 26

₁⁵∫ (2x)/ (x² +1)² dx = ₂ ²⁶ ∫u⁻² du
= [- 1/ u ]²⁶₂ = - [ 1/u ]²⁶ ₂ = - (1/26  - 1/2) = - (-6/13)
= 6/13