Question

if tan theta is 1 by root 5 and theta lies in the second quadrant find the value of cos theta

Answer 1

Q= theta
tanQ=1/5
TanQ= p/b
p/b=1/5
so, by pythagoreas theorem
h= underrot p^2+b^2
h=

$\sqrt{26}$

cosQ= b/h
=
$5 \div \sqrt{26}$

since Q lies in secod quadrant
so cosQ=
$- 5 \div \sqrt{26}$
ans.