Question

if cos A is equals to 2 / 5 find the value of 4 + 4tan square A

Answer 1

cosA=2/5

4+4tan^2A
=4(1+tan^2A)
=4×sec^2A
=4×1/cos^2A
=4×1/(2/5)^2
=4×1/4/25
=4×25/4
=25

therefore 4+4tan^2A=25
I hope it will help you
pls make it brainlist

Answer 2

cosA = 2/5

$sina = \sqrt{21} \div 5$

$tana = sina \div cosa$

$tana = \sqrt{21} \div 2$

$4 + 4tan {}^{2} a$

$4 + 4( \sqrt{21} \div 2) {}^{2}$

$4 + 21 = 25$