Question

In ❑ ABC , if a = 10, b = 8, c = 6 then find the values of
i) cos C ii) sin A/2 iii) cos A/2 iv) tan A/2 v)A (ABC) vi) sin C vii) tan C

Answer 1

Step-by-step explanation:

The value of cot15

∘

.cot20

∘

.cot70

∘

.cot75

∘

is

=(cot15

∘

.cot75

∘

)(cot20

∘

cot70

∘

)

Now cot75

∘

=tan15

∘

and cot70

∘

=tan20

∘

. cot(90−θ)=tanθ

Therefore, the given expression can be written as

(cot15

∘

tan15

∘

)(cot20

∘

tan20

∘

)

=1×1=1