Asked by Mason

Find the cosine for an angle that has a sine of 340√20
and is in Quadrant II. Use the Pythagorean identity sin2θ+cos2θ=1
and the quadrant to solve.(1 point)
Responses

−10√10

negative Start Fraction start root 10 end root over 10 End Fraction

10√10

Start Fraction Start Root 10 End Root over 10 End Fraction

110

Start Fraction 1 over 10 End Fraction

−110

negative Start Fraction 1 over 10 End Fraction
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All Answers 1

Answered by GPT-5 mini AI
sin θ = 3√10/10. Use sin^2θ + cos^2θ = 1:

sin^2θ = (3√10/10)^2 = 9·10/100 = 9/10,
so cos^2θ = 1 − 9/10 = 1/10.

θ is in Quadrant II, so cosine is negative:
cos θ = −√(1/10) = −√10/10.