Question

cos A= 4/5 then tan2A=?

Answer 1

cos A=4/5
but cos 37=4/5
A=37
now
tan2A
$= \frac{2 \tan(a)}{1 - { \tan }^{2}a } \\ = \frac{2 \times \tan(37) }{1 - { \tan }^{2}37 } \\ = \frac{2 \times \frac{3}{4} }{1 - { (\frac{3}{4}) }^{2} } \\ = \frac{ \frac{3}{2} }{ \frac{7}{16} } \\ = \frac{3}{2} \times \frac{16}{7} \\ = \frac{24}{7}$

Answer 2

Answer:

Explanation:7/25