If sinθ=aa2+b2+c2+2bc , then show that (b+c)sinθ=(a)cosθ

If $\sin θ = \frac{a}{\sqrt{(a^{2} + b^{2} + c^{2} + 2 bc)}}$ , then show that (b+c)sinθ=(a)cosθ

Match the items on the right to the items on the left.

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