Ok So i finished my questions and was wondering if someone could check my work to see if i did it right.(adsbygoogle = window.adsbygoogle || []).push({});

Question: If CosA= 1/3, with 0<A<pie/2, and SinB=1/4, with pie/2<B<pie, Calculate sin(A+B)

My Solution:

Sin(A+B)= SinACosB + CosASinB

=SinACosB + (1/3)(1/4)

SinACosB + 1/12

Ok Now i drew Triangle A and labeled the bottom 1 and hypotaneous 3. Then used the theorum to get the last side is square root 8.

I made Triangle B and labelled hypotaneous 4, adjacent side being 1 and used theorum to get the opposite side to be square root of 15.

=(square root8/3)(square root15/4) +1/12

=(square root120/12) + 1/12

to get my final answer of squareroot 120 +1 /12.

Is that correct?

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# Homework Help: Did i do it correct

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