What is sin θ for this θ = cos^-1(-3/5)?

Question 99

MediumOriginal question

Let $\theta = \cos^{-1}\left(-\frac{3}{5}\right)$ .

What is $\sin \theta$ for this $\theta = \cos^{-1}\left(-\frac{3}{5}\right)$ ?

- \frac{4}{5}

Correct answerYour answer

\frac{3}{5}

Correct answerYour answer

\frac{3}{4}

Correct answerYour answer

\frac{4}{5}

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

Worth noting

$-\frac{4}{5}$ copies the minus sign from the cosine; on $[0, \pi]$ the sine is never negative.

Ten questions from Inverse Trigonometric Functions, at your own pace.

Ten questions from Inverse Trigonometric Functions, at your own pace.