Question

tan{ cos^-1(4/5) + tan^-1 (2/3)} =?

Answer 1

Let \(\cos^-1\large\frac{4}{5}\) be \(\alpha\).
Then \(\cos\alpha=\large\frac{4}{5}\)
k?

Answer 2

ok

Answer 3

\(\tan\alpha=\large\frac{3}{4}\)
Let \(\tan^-1\large\frac{2}{3}\) be \(\beta\).
Then \(\tan\beta=\large\frac{2}{3}\)
Nw \(\tan(\alpha+\beta)=\large\frac{\tan\alpha+tan\beta}{1-\tan\alpha\tan\beta}\)
\( =\LARGE\frac{\frac{3}{4}+\frac{2}{3}}{1-(\frac{3}{4}*\frac{2}{3})}\)
Can u do nw?