If 3sin theta +4 cos theta=5. Find the value of sin theta +cos theta
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let theta = A
3 sin A + 4 Cos A = 5 to find sin A + cos A
3 SinA = 5 - 4 Cos A
9 Sin² A = 25 - 40 Cos A + 16 Cos²A
25 Cos² A - 40 Cos A + 16 = 0
Cos A = [20 +- √(400 - 400]/25 = 4/5
Sin A = [5 - 4*4/5 ]/3 = 3/5
Sin A + Cos A = 7/5
3 sin A + 4 Cos A = 5 to find sin A + cos A
3 SinA = 5 - 4 Cos A
9 Sin² A = 25 - 40 Cos A + 16 Cos²A
25 Cos² A - 40 Cos A + 16 = 0
Cos A = [20 +- √(400 - 400]/25 = 4/5
Sin A = [5 - 4*4/5 ]/3 = 3/5
Sin A + Cos A = 7/5
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