The reciprocal function of cosine is [...]\text{[...]}[...].
A
5\mathbf{\sqrt5}5
B
Divide every term by cos2θ\cos^2\thetacos2θ.
C
sec2θ≡1+tan2θ\mathbf{\sec^2\theta\equiv1+\tan^2\theta}sec2θ≡1+tan2θ
D
The reciprocal function of cosine is secθ=1cosθ\boxed{\sec\theta=\frac{1}{\cos\theta}}secθ=cosθ1.
1.8.5 Trigonometric identities Flashcards
Flashcards for AQA A Level Maths 1.8.5 Trigonometric identities, covering the key formulae, methods and definitions you need to recall for Paper 1, Paper 2 and Paper 3. 23 cards, matched to the AQA A Level Maths (7357) specification. Recall questions account for roughly 50% of marks at A Level Maths, so these target the marks you can secure before the paper starts.