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Work Shown:
sin(A)*cot(A)
sin(A)*( cos(A)/sin(A) )
cos(A)
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Basically I replaced cot(A) with cos(A)/sin(A). Then the sin(A) terms canceled out leaving cos(A) behind.
Answer:
cosA
Step-by-step explanation:
Using the identity
cotA = [tex]\frac{cosA}{sinA}[/tex] , then
sinA × cotA
= sinA × [tex]\frac{cosA}{sinA}[/tex] ( cancel sinA )
= cosA