Question

6. Show that sin*; 4 xCost Cost®,4 xsins
If A, B, C, are the interior angle of A triangle ABC​

Answer 1

Step-by-step explanation:

Given A,B,C are the interior angles of △ABC

⟹A+B+C=180

∘

⟹B+C=180 ∘ −ALHS=sin( 2B+C

)=sin(

2

180

∘

−A

)=sin(90

∘

−

2

A

)=cos

2

A

=RHS