Double Angles-Not sure how to start problem

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So the question states:

Given that sin2A=2sinAcosA and cos2A=cos²A-sin²A,evaluate this without using your calculator: 2sin15cos15


I was missing when we did these so I'm very confused, do you sub this into the equation but how do you move forward then?The answer on the back of the book is a half but I don't get that on my calculator either.Thanks for your help!

 

[Deleted member 4993]

So the question states:

Given that sin2A=2sinAcosA and cos2A=cos²A-sin²A,evaluate this without using your calculator: 2sin15cos15


I was missing when we did these so I'm very confused, do you sub this into the equation but how do you move forward then?The answer on the back of the book is a half but I don't get that on my calculator either.Thanks for your help!

Do you understand the given equations? Specifically:

sin(2A) = 2 * sin(A) * cos(A)

If A = 15

What does the equation above become?