Question

formula of 2sinA.cosB

Answer 1

Hi ,

We know that,
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If A and B are any two angles then

i) Sin( A + B ) = sinA cosB +CosAsinB

ii ) sin(A- B ) = sinAcosB - CosAsinB

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Sin(A +B ) + sin(A - B )

= SinAcosB+cosAsinB + sinAcosB

- cosAsinB

= 2sinAcosB

Therefore ,

2sinAcosB = sin( A+B ) + sin( A- B )

I hope this helps you.

:)