Question

if anyone can answer this would be having a good day!
if sinA+sin²A+sin³A=1
P.T
Cos^(6)A-4Cos⁴+8cos²A=4
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Answer 1

Sin^2 A = - (sinA+Sin^3A)

Sin^2A + Cos^2A = 1

Cos^2A = 1-sin^2A

CosA = 1 - sinA

(1- sin^2A)^3 - 4(1-Sin^2A)^2 + 8(1-sin^2A)

[1 - (sin^2A)^3 - 3(-sin^2A)sin^2A + 1] - [4(1- 2sin^2A + (sin^2A)^2] + [8- 8sin^2A]

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