Question

Cosec a + cot a = 2, find the value of
cosec a = ?
a)1/2
b)1/4
c)1
d)2

Answer 1

we can write it as

1/sina + cosa/sina = 2

so 1+ cosa=2sina

now square both sides....we get 1 + 2cosa + cos^2 a = 4sin^2 a...1

now sin ^a + cos^a =1

so use this in 1

we end up with a quadratic in cosa which can be solved easily

once cosa is calculated coseca can also be calculated

cosa comes -1,3/5