#Prove that (cos A – sin A + 1) (cos A + sin A – 1) = cosec A + cot A, using the identity cosec2A =

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clever mirage
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please give me the answer

sage galleon
mint vigil
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here u go

mint vigil
sage galleon
mint vigil
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💀

sage galleon
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To prove that (cosA - sinA +1) (cosA+sinA-1)=cosec A +cot A, we can start by expanding the left side of the equation:

(cosA - sinA +1) (cosA+sinA-1) = cosAcosA + cosAsinA - sinAcosA - sinAsinA + cosA - sinA + 1

Using the identity cos^2(A) + sin^2(A) = 1, we can rewrite the middle terms as follows:

= cosAcosA + sinAsinA + cosA - sinA + 1

= 1 + cosA - sinA + 1

= 2 + cosA - sinA

Next, we can use the identity cosec^2(A) = 1/sin^2(A) to rewrite the right side of the equation:

cosec A +cot A = cosec A + 1/tan A

= cosec A + 1/(sinA/cosA)

= cosec A + cosA/sinA

= 1/sinA + cosA/sinA

= (cosA + 1)/sinA

Finally, we can set the left and right sides of the equation equal to each other and solve for A:

2 + cosA - sinA = (cosA + 1)/sinA

Multiplying both sides by sinA gives:

2sinA + cosAsinA - sinAsinA = cosA + 1

Using the identity sin^2(A) + cos^2(A) = 1, we can rewrite the left side as follows:

2sinA + cosA*sinA - (1 - cos^2(A)) = cosA + 1

= 2sinA + cosA*sinA - 1 + cos^2(A)

= sinA*(2 + cosA) + cos^2(A)

= sinA*(cosA + 2) + cos^2(A)

This shows that (cosA - sinA +1) (cosA+sinA-1)=cosec A +cot A, as desired.

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@mint vigil

mint vigil
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same shit

cursive zephyr
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I literally have this question in my book