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2 years ago

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Prove this identity sin(2A)=2sinAcosA.

1 answer:

34kurt2 years ago

7 0

The solution for proving the identity is as follows:

sin(2A) = sin(A + A)
As sin(a + b) = sinacosb + sinbcosa,
<span>sin(A + A) = sinAcosA + sinAcosA
</span>
<span>Therefore, sin(2A) = 2sinAcosA

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your inquiries and questions soon. Have a nice day ahead!
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Step-by-step explanation:

For a start simplify each of the roots:

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Now simplify the expression in steps:

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$20\sqrt{2}-\cfrac{609*\sqrt{2} }{40\sqrt{2} *\sqrt{2} } =$

$20\sqrt{2}-\cfrac{609\sqrt{2} }{40*2 } =$

$20\sqrt{2}-\cfrac{609\sqrt{2} }{80 } =$

$\sqrt{2} (20-7\cfrac{49}{80} )=$

$\sqrt{2} *12\cfrac{31}{80} =$

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