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Given that sin 0 = 21/29, what is the value of cose, for 0° <0<90°? please help

Given that sin 0 = 21/29, what is the value of cose, for 0° <0<90°? please help-example-1
User Sergio Lucero
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1 Answer

16 votes
16 votes

Answer:

3rd option

Explanation:

Using the identity

sin²x + cos²x = 1 ( subtract sin²x from both sides )

cos²x = 1 - sin²x ( take the square root of both sides )

cosx = ±
√(1-sin^2x)

Given

sinθ =
(21)/(29) and 0 < θ < 90 , then

cosθ

=
\sqrt{1-((21)/(29))^2 }

=
\sqrt{1-(441)/(841) }

=
\sqrt{(400)/(841) } =
(√(400) )/(841) =
(20)/(29)

User Gemmakbarlow
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2.1k points