Coefficient of x5 in the product of (1+2x)6 (1−x)7
(1+2x)6 (1−x) 7
Expanding using Binomial theorem
Now, the coefficient of x5 in the product is
=1×(−21)+12×35+60×(−35)+160×21+240×(−7)+192×1
=−21+420−2100+3360−1680+192
=171
The coefficient of x5 is 171.