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Prove the following: sin4θ +2sin2θ . cos2θ = 1 − cos4θ

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Question

Prove the following:

sin4θ +2sin2θ . cos2θ = 1 − cos4θ

Sum
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Solution

L.H.S. =sin4θ +2sin2θ . cos2θ

= sin2θ(sin2θ + 2cos2θ)

= (sin2θ) (sin2θ + cos2θ + cos2θ)

= (1 – cos2θ) (1 + cos2θ)

= 1 – cos4θ

= R.H.S.

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Chapter 2: Trigonometry - 1 - MISCELLANEOUS EXERCISE - 2 [Page 34]

APPEARS IN

Balbharati Mathematics and Statistics (Arts and Science) Part 1 [English] Standard 11 Maharashtra State Board
Chapter 2 Trigonometry - 1
MISCELLANEOUS EXERCISE - 2 | Q 10) viii) | Page 34

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