If θ is an acute angle and Cos θ = 39/89 , what is the value of sin θ ?

If θ is an acute angle and Cos θ = 39/89 , what is the…

If $\theta$ is an acute angle and Cos $\theta$ = $\frac{39}{89}$ , what is the value of sin $\theta$ ?

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Correct answer: C

Explanation

The correct answer is Option 3 i.e. $\frac{80}{89}$ .

cos θ = 39/89

⇒ cos²θ = (39/89)² = 1521/7921

⇒ sin²θ = 1 - cos²θ = 1 - 1521/7921 = 6400/7921

⇒ sin θ = √(6400/7921) = 80/89