N
nh0c_bu0n1995


1/
I=\int_{}^{}từ 0 tới pi/3 => xsin2xdx/cos mủ 4x
2/
log(2x^2+x-1)+log(2x-1)^2=4
.....2x-1.................2+1
I=\int_{}^{}từ 0 tới pi/3 => xsin2xdx/cos mủ 4x
2/
log(2x^2+x-1)+log(2x-1)^2=4
.....2x-1.................2+1