Cot A +Cosec A-1/cot A -codec A +1= 1+cos A/sin A
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Step-by-step explanation:
LHS : cot A + cosec A - 1 / cot A - cosec A + 1
[ (cosA/sinA) +(1/sinA) – 1] / [(cosA/sinA) -(1/sinA) + 1]
{ [cosA + 1-sinA ]/sinA} / { [cosA – 1+sinA ]/sinA }
{ [cosA + 1-sinA ]/sinA} * sinA/[cosA – 1+sinA ]
[cosA + 1-sinA ]/ [cosA – 1+sinA ]
(cosA- sinA) +1/ (cosA+sinA) – 1
{ (cosA- sinA) +1/ (cosA+sinA) – 1}* {(cosA+sinA) +1 /(cosA+sinA) +1}
( Rationalising it by"(cosA+sinA) +1")
{(cosA- sinA)(cosA+sinA) +(cosA- sinA) +(cosA- sinA) +1} /[(cosA+sinA) – 1][(cosA+sinA) +1]
{(cos2A- sin2A)+2cosA+sinA- sinA +1}/ (cosA+sinA)2 -1
{ cos2A-(1- cos2A) + 2cosA+1} / (cos2A+sin2A+2sinA cosA) -1
{ cos2A-1+ cos2A + 2cosA+1} / 2sinA cosA +1 – 1
2cos2A + 2cosA / 2sinA cosA
2 cosA (cosA +1) / 2cosA (sinA)
1 + cos A / sin A LHS = RHS (Hence proved)
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