1.)cos alpha+sin alpha*tan alpha=
2.) 1/(1+tan^2 alpha)=
3.)tan alpha/Wurzel(1+tan^2 alpha)=
4.)sin^4 alpha−cos^4 alpha=
+26387 4.) sin^4 alpha−cos^4 alpha=
$$\small{\text{$
\begin{array}{rcl}
\sin^4{ (\alpha) } - \cos^4{ ( \alpha ) } \\
&=& - (~ \cos^4{ ( \alpha ) } - \sin^4{ (\alpha) } ~)\\
&=& - (~
( \cos^2{ ( \alpha ) } - \sin^2{ (\alpha) } ) \cdot
( \cos^2{ ( \alpha ) } + \sin^2{ (\alpha) } )
~)\\\\
&&$Formeln:\\\\
&&$~\boxed{\mathbf{ \cos^2{ ( \alpha ) } - \sin^2{ (\alpha) } = \cos{(2\cdot\alpha)} }}\\
&&$~\boxed{\mathbf{ \cos^2{ ( \alpha ) } + \sin^2{ (\alpha) } = 1 }}\\\\
\sin^4{ (\alpha) } - \cos^4{ ( \alpha ) }&=&-\cos{(2\cdot\alpha)}
\end{array}
$}}$$
+26387 4.) sin^4 alpha−cos^4 alpha=
$$\small{\text{$
\begin{array}{rcl}
\sin^4{ (\alpha) } - \cos^4{ ( \alpha ) } \\
&=& - (~ \cos^4{ ( \alpha ) } - \sin^4{ (\alpha) } ~)\\
&=& - (~
( \cos^2{ ( \alpha ) } - \sin^2{ (\alpha) } ) \cdot
( \cos^2{ ( \alpha ) } + \sin^2{ (\alpha) } )
~)\\\\
&&$Formeln:\\\\
&&$~\boxed{\mathbf{ \cos^2{ ( \alpha ) } - \sin^2{ (\alpha) } = \cos{(2\cdot\alpha)} }}\\
&&$~\boxed{\mathbf{ \cos^2{ ( \alpha ) } + \sin^2{ (\alpha) } = 1 }}\\\\
\sin^4{ (\alpha) } - \cos^4{ ( \alpha ) }&=&-\cos{(2\cdot\alpha)}
\end{array}
$}}$$
