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> Finding $\displaystyle \int^{\infty}\_{0}\bigg(\frac{1-\cos 7x}{x}\bigg)e^{-x}dx$
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Plan

$$I =\int^{\infty}\_{0}\frac{1}{x}\bigg(1-\frac{(7x)^2}{2!}+\frac{(7x)^4}{4!}+\cdots \bigg)\bigg(1-\frac{x}{1!}+\frac{x^2}{2!}+\cdots \bigg)dx$$

How do i solve it Help me please