CosA - sinA + 1 / cosA + sinA - 1 = cosecA + cotA
Answers
Answered by
37
This is a trig. identity
(cosA-sinA+1) /(cosA+sinA-1)=cosecA+cotA
LHS
= (cosA-sinA+1) /(cosA+sinA-1)
Multipy the numerator and denominator by (cosA-sinA+1)
(cosA-sinA+1)^2 /[(cosA+sinA-1)(cosA-sinA+1)]
= (cos^2A + sin^2A + 1 - 2sinAcosA + 2cosA - 2sinA) / (cos^2A - sin^2A - 2sinA - 1)
= (2- 2sinAcosA + 2cosA - 2sinA) / (-2sin^2A - 2sinA)
Divide the numerator and denominator by -2
(sinAcosA + sinA - cosA - 1) / (sinA(1+sinA))
= (sinA(cosA+1) + 1(cosA+1))/(sinA(1+sinA))
= (1+sinA)(1+cosA) / (sinA(1+sinA))
= (1+cosA)/sinA
= 1/sinA + cosA/sinA
= cosecA + cotA
= RHS
(cosA-sinA+1) /(cosA+sinA-1)=cosecA+cotA
LHS
= (cosA-sinA+1) /(cosA+sinA-1)
Multipy the numerator and denominator by (cosA-sinA+1)
(cosA-sinA+1)^2 /[(cosA+sinA-1)(cosA-sinA+1)]
= (cos^2A + sin^2A + 1 - 2sinAcosA + 2cosA - 2sinA) / (cos^2A - sin^2A - 2sinA - 1)
= (2- 2sinAcosA + 2cosA - 2sinA) / (-2sin^2A - 2sinA)
Divide the numerator and denominator by -2
(sinAcosA + sinA - cosA - 1) / (sinA(1+sinA))
= (sinA(cosA+1) + 1(cosA+1))/(sinA(1+sinA))
= (1+sinA)(1+cosA) / (sinA(1+sinA))
= (1+cosA)/sinA
= 1/sinA + cosA/sinA
= cosecA + cotA
= RHS
Answered by
1
(cosA-sinA+1)^2 /[(cosA+sinA-1)(cosA-sinA+1)]
= (cos^2A + sin^2A + 1 - 2sinAcosA + 2cosA - 2sinA) / (cos^2A - sin^2A - 2sinA - 1)
= (2- 2sinAcosA + 2cosA - 2sinA) / (-2sin^2A - 2sinA)
Divide the numerator and denominator by -2
(sinAcosA + sinA - cosA - 1) / (sinA(1+sinA))
= (sinA(cosA+1) + 1(cosA+1))/(sinA(1+sinA))
= (1+sinA)(1+cosA) / (sinA(1+sinA))
= (1+cosA)/sinA
= 1/sinA + cosA/sinA
= cosecA +
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