Help with trigonometric equations

Nov 2012
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0
If sinA =1/2 and cosB =1/2, then the value of A + B = ?(Degree)
 
Jul 2010
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St. Augustine, FL., U.S.A.'s oldest city
If we restrict the angles to the first quadrant, we may use the co-function identity to state:

\(\displaystyle \sin(A)=\cos(B)=\sin\left(90^{ \circ}-B\right)\)

Hence:

\(\displaystyle A=90^{\circ}-B\)

\(\displaystyle A+B=90^{\circ}\)
 

skipjack

Forum Staff
Dec 2006
21,482
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Without that restriction, the sum (modulo 360°) is 90°, 210° or 330°.
 
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Dec 2015
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Earth
\(\displaystyle \arcsin(x)+\arccos(x)=\pi /2 \).