Question 772771
verify the identity and justify each step for tan Q + cot Q = 1/sin Q*cos Q
also for cos[Q-pi/2] = -tan Q
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Start with left-hand side:
{{{tan Q+cot Q=(sin Q/cos Q)+(cos Q/sin Q)=(sin^2(Q)+cos^2(Q))/(sin Q*cos Q)=1/(sin Q*cos Q)}}}
verified: 
left-hand side=right-hand side
note: Identity: sin^2Q+cos^2Q=1