Evaluate $\int \sin(3x)\cos(4x) \,dx$

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Evaluate $$\int \sin(3x) \cos(4x) \; \mathrm{d}x$$ I do not know how to solve this as a whole. I tried all the substitutions known to me.

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Use the following identity:$\color{blue}{\quad \cos \left(\alpha\right)\sin \left(\beta\right)=\frac{\sin \left(\alpha+\beta\right)-\sin \left(\alpha-\beta\right)}{2}}$

$$\int \sin \left(3x\right)\cos \left(4x\right)dx=\frac{1}{2}\int \sin \left(4x+3x\right)-\sin \left(4x-3x\right)dx=\color{red}{\frac{1}{2}\left(\cos \left(x\right)-\frac{1}{7}\cos \left(7x\right)\right)+C}$$