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\frac { \operatorname { sin } 7 \theta - \operatorname { sin } 5 \theta } { \operatorname { cos } 7 \theta + \operatorname { cos } 5 \theta } = \operatorname { tan } \theta |
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Answer» LHS sin7x-sin5x/cos7x+cos5x=2cos(7x+5x/2).sin(7x-5x/2)/2cos(7x+5x/2).cos(7x-5x/2)i.e; cos(12x/2).sin(2x/2)/cos(12x/2).cos(2x/2)i.e., cos(6x).sin(x)/cos(6x).cos(x)i.e.,sinx/cosxi.e.,tanx=RHS similarly, |
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