Question

Find the value of
¡) sine15°
¡¡) tan225°
¡¡¡) cos390°
¡v) cosec330°
v) cot1020°
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Answer 1

Answer:

I)sin15°=sin(45°-30°)

then,sin(A-B)=sinA.cosB+CosA.sinB

or, 1/√2.1/2+1√2.√3/2

or,1/2√2+√3/2√2

or,√3+2/2√2

Answer 2

Answer:

i) sine15 = sine(45-30)

= sine(45)cos(30) - cos(45)sine(30)

1/√2×√3/2 - 1/√2×1/2

=√3-1/2√2