1/cosec A -cot A-1/sin A=1/sin A -1/cosecA+cotA ,Prove it by using trigonometric identities.
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LHS = 1/(cosecA - cotA) - 1/sinA
we know, cosec²A - cot²A = 1......(i)
= (cosec²A - cot²A)/(cosecA - cotA) - 1/sinA [from equation (i), ]
= (cosecA - cotA)(cosecA + cotA)/(cosecA - cotA) - 1/sinA
= (cosecA + cotA) - 1/sinA
= cosecA + cotA - cosecA [ as 1/sinA = cosecA]
= cotA
= cosecA - (cosecA - cotA)/1
= cosecA - (cosecA - cotA)/(cosec²A - cotA)
= 1/sinA - (cosecA - cotA)/(cosecA - cotA)(cosecA + cotA)
= 1/sinA - 1/(cosecA + cotA) = RHS
we know, cosec²A - cot²A = 1......(i)
= (cosec²A - cot²A)/(cosecA - cotA) - 1/sinA [from equation (i), ]
= (cosecA - cotA)(cosecA + cotA)/(cosecA - cotA) - 1/sinA
= (cosecA + cotA) - 1/sinA
= cosecA + cotA - cosecA [ as 1/sinA = cosecA]
= cotA
= cosecA - (cosecA - cotA)/1
= cosecA - (cosecA - cotA)/(cosec²A - cotA)
= 1/sinA - (cosecA - cotA)/(cosecA - cotA)(cosecA + cotA)
= 1/sinA - 1/(cosecA + cotA) = RHS
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Answer:
At the 9th step it is cosec ^2-cot^2
Everything is ok but it is little mistake.
Step-by-step explanation:
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