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![]() | \(\sin x=1\Leftrightarrow x=\dfrac{\pi}{2}+k2\pi,\,k\in\mathbb{Z}\) |
![]() | \(\sin x=1\Leftrightarrow x=\dfrac{\pi}{2}+k\pi,\,k\in\mathbb{Z}\) |
![]() | \(\cos x=1\Leftrightarrow x=k2\pi,\,k\in\mathbb{Z}\) |
![]() | \(\cos x=0\Leftrightarrow x=\dfrac{\pi}{2}+k\pi,\,k\in\mathbb{Z}\) |