三角函数的倍角问题

青青子衿

已知$/cos17x=f(/cosx)
则/sin17x=f(/sinx)$
\(\color{blue}{/cos17x=f(/cos x)\phantom{\star}/sin17x=f(/sin x)}\)
\[\cancelto{cos17x}{/cos17x}\]
\(\color{green}{\cos17x=f(\cos x)\phantom{\star}\sin17x=f(\sin x)}\)

其妙

回复 1# 青青子衿
，$\cos17x=f(\cos x) $，则$\sin17x=f(\sin x)$，反斜杠的输入问题