Question

How to solve:

Sin(70)Cos(10) - Sin(10)Cos(70)

Can you simplify to Sin(60)Cos(-60) or can you not do that?

Answer 1

Sin(70)Cos(10) - Sin(10)Cos(70)

is the same as

Sin(70)Cos(10) - Cos(70)Sin(10)

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use

sin(A-B) = sin(A)*cos(B) - cos(A)*sin(B)

Answer 2

So I get

Sin(70-10) = Sin70Cos10 - Cos70Sin10

Sin (70-10) = Sin(60) = Sq. 3/2

Did I do that right?

Answer 3

you did that perfectly, the answer is \[\Large \frac{\sqrt{3}}{2}\]

Answer 4

Thank you once again!

Answer 5

sure thing