If ∫1−x9x1+x9dx=Alog⁡|x|+Blog⁡1+x9+C, then the value of AB is equal to

∫1−x9x1+x9dx=Alog⁡|x|+Blog⁡1+x9+CDifferentiating both the sides, we get1−x9x1+x9=Ax+9Bx81+x9⇒1−x9=A1+x9+9Bx9⇒A=1,−1=A+9B⇒A=1,B=−29Thus, AB=-92=-4.5