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. Oc0s10° + sin 10०0810? - sin 10°........ |
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Answer» LHS = ( Cos 10 + Sin 10 ) / ( Cos 10 - Sin 10 ) { Multiply numerator and and denominator with 1 / Cos 10 } = [ 1 /Cos 10 ( Cos 10 + Sin 10 ) ] / [ 1/Cos 10 ( Cos 10 - Sin 10 ) ] = [ Cos10 / Cos10 + Sin10 / Cos10 ] / [ Cos10 / Cos10 - Sin10 / Cos10 ] = ( 1 + tan10 ) / ( 1 - tan 10 ) [ since sin 10 / cos 10 = tan 10 ] = ( tan 45 + tan 10 ) / ( 1 - tan 45 tan 10 ) [ since tan 45 = 1 ] = tan ( 45 + 10 ) [ since tan ( A + B ) = (tanA + tan B ) / (1 - tanAtanB)] = tan 55 = tan ( 90 - 35 ) = cot 35 [ since tan ( 90 - A ) = cot A ] |
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