Question

answer this question please​

Answer 1

Answer:

cos @=3^1/2 /2

so, @= 30°

therefore sin 2@= sin60°

sin60°=3^1/2 / 2

Same as cos@

Answer 2

Ans:

Step-by-step explanation:

$if\\cos=\sqrt{3} /2\\\\\\then$

$sinA=\sqrt{1-cos^2A}$

$sinA=1/2$

$sin2A=2sinAcosA$

$sin2A=2(1/2)(\sqrt{3}/2)$

$thus,\\\\\\sin2A=\sqrt{3} /2$