49) $(\sin\theta+\cos\theta)^2=1+\sin2\theta$
Left Side:
\begin{align*}
(\sin\theta+\cos\theta)^2=\sin^2\theta+2c\cos\theta\sin\theta+cos^2\theta=1+2\cos\theta\sin\theta
\end{align*}
This can either be $1$ or I can power reduce it. I don't know.
Right Side:
\begin{align*}
1+\sin2\theta=1+2\sin\theta\cos\theta
\end{align*}
Thank you!
Answer
Open parentheses and use:
$$(1)\,\,\sin^2x+\cos^2x=1$$
$$(2)\,\,\sin 2x=2\sin x\cos x$$
No comments:
Post a Comment