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Sin +cos. =1find sin -cos |
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Answer» (Sin+cos)²=sin²+cos²+2sin.cos ;(1)²=1+2sin.cos ;1=1+2sin.cos ;0=2sin.cos ; now, (sin-cos)²=sin²+cos²-2sin.cos (sin-cos)²=1-0 (sin-cos)²=1 sin-cos = 1 Sin-cos=-1 |
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