Question

sin^4a - cos^4 a + 1 = 2 sin^2a

PROVE
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Answer 1

hey mate

here is the answer...

Answer:

to prove:

sin⁴ a-cos⁴ a+1=2 sin²a

LHS;

sin⁴a-cos⁴a+1

=>(sin²a)²-(cos ²a)²+1

[(a²-b²)=(a+b)(a-b)]

=>(sin²a+cos²a)(sin²a-cos²a)+1

=>1(sin²a-cos²a)+1

[sin²a+cos²a=1]

=>sin²a-cos²a+sin²a+cos²a

=>2 sin²a [RHS]

thus, proved!

Answer 2

Hey mate!

Refer the attachment!

Hope it helps u..