Question 1154938
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(1a) Given sinx = -2/3 in quadrant III, use sin^2 + cos^2 = 1 to find cosx, and give it the negative value since cosine is negative in quadrant III.<br>
(1b) Given cosy 4/7 in quadrant IV, use sin^2 + cos^2 = 1 to find sinx, and give it the negative value since sine is negative in quadrant IV.<br>
(2a) Find sin(x+y), using sin(x+y) = sinx*cosy+cosx*siny<br>
(2b) Find cos(x+y), using cos(x+y) = cosx*cosy-sinx*siny<br>
(3) Find tan (x+y), using tan(x+y) = sin(x+y)/cos(x+y)<br>
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