Question

cos a is 2/5 find 4+4tan square a

Answer 1

Cos a= 2/5
Now, 4+4 tan²a
=4(1+tan²a)...
4(sec²a)..... (1+tan²) =sec²
4((5/2)²)... Sec =1/cos
4(25/4)
25 is the answer
Plz mark as brainliest if it will help you

Answer 2

cos a =2/5
cos square a + sin square a =1
sin square a=1-4/25. ( cos square a =9/25)
sin square a=21/25
sin a =
$\sqrt{21} \div 25$
tan a=sin a/ cos a
$\sqrt{21} \div 4$
tan square a=
$21 \div 16$
4+4tan square a=
$4 + (21 \div 4)$
taking lcm
$37 \div 4$
=
$9.25$