Question

show that (1+cot^2 a) (1-cos a) (1+cos a) =1​

Answer 1

Answer:

1+cot^2 a = cosec^2 a

(1+cos a)(1-cos a)= 1-cos^2 a =sin^2 a

cosec^2 a x sin^2 a

1/sin^2 a x sin^2 a

sins will be cancelled

so answer is 1

Step-by-step explanation:

Answer 2

Answer:

LHS = (1+cot²A)(1-cosA)(1+cosA)

/* By algebraic identity:

(a-b)(a+b)=a²-b² */

= (1+cot²A)(1-cos²A)

/* By Trigonometric identity:

1-cos²A = sin²A */

= cosec²A× sin²A

= 1

/* cosec²A × sin²A = 1*/

= RHS

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