Easy -1.8 This is a straightforward application of the Pythagorean identity sin²θ + cos²θ = 1 with basic quadrant knowledge. Worth only 1 mark, multiple choice format, and requires minimal calculation: cos²θ = 1 - 16/25 = 9/25, so cosθ = ±3/5, negative in second quadrant. This is below average difficulty, being a routine recall question with no problem-solving element.
It is given that \(\sin \theta = \frac{4}{5}\) and \(90° < \theta < 180°\)
Find the value of \(\cos \theta\)
Circle your answer.
[1 mark]
\(-\frac{3}{4}\) \qquad \(-\frac{3}{5}\) \qquad \(\frac{3}{5}\) \qquad \(\frac{3}{4}\)
It is given that $\sin \theta = \frac{4}{5}$ and $90° < \theta < 180°$
Find the value of $\cos \theta$
Circle your answer.
[1 mark]
$-\frac{3}{4}$ \qquad $-\frac{3}{5}$ \qquad $\frac{3}{5}$ \qquad $\frac{3}{4}$
\hfill \mbox{\textit{AQA AS Paper 2 2023 Q2 [1]}}