Show that sin2A is equal to 2sinAcosA
This question requires you to use the trigonometric identity sin(A+B)=sinAcosB + sinBcosA. The difficulty in this problem is noticing that you need to substitute 2A for A+A and then you can simply put this into the trig identity. Doing this leads to you sin2A=sinAcosA + sinAcosA which is 2sinAcosA.
SL
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