Question

помогите
срочно
!!!!!!!!​

Answer 1

$\displaystyle\bf\\1)\\\\f(x)=\frac{Sin6x}{6x} \\\\\\f\Big(\frac{\pi }{3} \Big)=\frac{Sin\Big(6\cdot \dfrac{\pi }{3}\Big) }{6\cdot\dfrac{\pi }{3} } =\frac{Sin2\pi }{2\pi } =\frac{0}{2\pi } =0\\\\\\2)\\\\f(x)=Cos5x Cos2x-Sin2x Sin5x=Cos(5x+2x)= Cos7x$