Standard +0.3 This is a straightforward identity proof requiring conversion of reciprocal trig functions to sin/cos, algebraic manipulation, and recognition of the cos 2x double angle formula. It's slightly above average difficulty due to the reciprocal functions and multi-step algebra, but follows a standard proof pattern with no novel insight required.
Express the LHS in terms of either \(\cos x\) and \(\sin x\) or in terms of \(\tan x\)
B1
Use Pythagoras
M1
Obtain the given answer
A1
Total: 3
## Question 1:
| Answer | Mark | Guidance |
|--------|------|----------|
| Express the LHS in terms of either $\cos x$ and $\sin x$ or in terms of $\tan x$ | B1 | |
| Use Pythagoras | M1 | |
| Obtain the given answer | A1 | |
| **Total: 3** | | |
---