Question

Please solve this question

Answer 1

Hi,

Explanation:

integration by parts

`\displaystyle \int\limits {(ln(7*x))^2} \, dx \\=x*ln(7*x)^2-\int\limits {(x*2*ln(7x)*7)/(7x)} \, dx \\\\=x*ln(7*x)^2-2\int\limits {ln(7x)} \, dx \\\\=x*ln(7*x)^2-2[x*ln(7x)-\int\limits {(x*7)/(7x)} \, dx ]\\\\\boxed{=x*ln(7*x)^2-2*x*ln(7x)+2x+C }\\`