Question

Алгебра.................... ​

Answer 1

$5)\ \ y=-2cos\Big(\dfrac{1}{3}\, x-\frac{\pi }{20}\Big)\\\\T(cosx)=2\pi \ \ \ \Rightarrow \ \ \ T\Big(-2cos\Big(\dfrac{1}{3}\, x-\dfrac{\pi}{20}\Big)\Big)=\dfrac{2\pi}{1/3}=6\pi \\\\\\6)\ \ f(x)=\dfrac{x^6+5}{x}\ \ ,\ \ f(-x)=\dfrac{(-x)^6+5}{-x}=-\dfrac{x^6+5}{x}=-f(x)\ chetnaya\\\\\\f(x)=x^3\cdot sinx\ \ ,\ \ f(-x)=(-x)^3\cdot sin(-x)=-x^3\cdot (-sinx)=x^3\cdot sinx\\\\{}\qquad \qquad \qquad \qquad \quad f(-x)=f(x)\ \ cyetnaya$