Standard +0.3 This is a straightforward double angle equation requiring expansion of sin 2θ to 2sin θ cos θ, then simplifying with tan θ = sin θ/cos θ to get a basic trigonometric equation. It's slightly easier than average as it follows a standard procedure with no conceptual surprises, though it does require knowing the double angle formula and careful algebraic manipulation.
Simplify to obtain form \(c_1\sin^2\theta = c_2\cos\theta\) or equivalent
M1
Find at least one value of \(\theta\) from equation of form \(\sin\theta = k\)
M1
Obtain \(35.3°\) and \(144.7°\)
A1
And no others between \(0°\) and \(180°\). Unsupported answer receives 0 marks.
Total
4
## Question 2:
| Answer | Marks | Guidance |
|--------|-------|----------|
| Use $\sin 2\theta = 2\sin\theta\cos\theta$ | B1 | |
| Simplify to obtain form $c_1\sin^2\theta = c_2\cos\theta$ or equivalent | M1 | |
| Find at least one value of $\theta$ from equation of form $\sin\theta = k$ | M1 | |
| Obtain $35.3°$ and $144.7°$ | A1 | And no others between $0°$ and $180°$. Unsupported answer receives 0 marks. |
| **Total** | **4** | |
---