All the trig I need for AP Calculus AB

General Formula [7+8] cos α±β = cos α cos β ∓ sin α sin β [9] Proof of . tan α ± β . Prove Sum. and Difference. Given. tan α±β = sin α±β cos α±β ... Divide by (cos α cos β ) , then Simplify. tan α±β = sin α cos β ± cos α sin β cos α cos β ∓ sin α sin β . General Formula. tan α±β = tan α ± tan β 1 ... ................
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