Show That 1/(cosecA-cotA) - 1/sinA = 1/sinA - 1/(cosecA+cotA)
To prove 1/(cosecA-cotA) - 1/sinA = 1/sinA - 1/(cosecA+cotA) we will start from LHS
Answer: LHS = RHS, 1/(cosecA-cotA) - 1/sinA = 1/sinA - 1/(cosecA+cotA) = cotA
Let us see detailed explanation
Explanation:
Consider the LHS 1/(cosecA-cotA) - 1/sinA
= 1/ (1/sinA-cosA/sinA) - 1/sinA [∵ cosec A = 1/sin A and cot A = cos A /sin A ]
=1/ (1-cosA/sinA)-1/sinA [Simplifying ]
=sinA / (1-cosA) - 1/sinA
=(sin2A - 1+cosA ) /sinA (1-cosA)
=-cos2A+cosA/sinA(1-cosA)
On taking (1-cosA) common from both numerator and denominator and simplifying it, we get
=cosA/sinA = cotA
Consider RHS = 1/sinA-1/(cosecA+cotA)
=sinA-1/(1/sinA+cosA/sinA)
= 1/sinA - 1/(1+cosA/sinA)
= 1/sinA-sinA/(1+cosA)
=1+cosA-sin2A/sinA(1+cosA)
= (1-sin2A)+cosA/sinA(1+cosA)
On taking (1+cosA) common from both numerator and denominator and simplifying it, we get
cosA/sinA = cot A
Hence proved
LHS=RHS
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