Using two points, the gradient of a straight line is [...]\text{[...]}[...].
A
666.
B
The concavity must change across x=ax=ax=a.
C
Using two points, the gradient of a straight line is y2−y1x2−x1\boxed{\frac{y_2-y_1}{x_2-x_1}}x2−x1y2−y1.
D
Below the xxx-axis, since f′(x)<0f'(x)<0f′(x)<0.
1.7.1 Differentiation Flashcards
Flashcards for WJEC A Level Maths 1.7.1 Differentiation, covering the key formulae, methods and definitions you need to recall for AS Unit 1, AS Unit 2, A2 Unit 3 and A2 Unit 4. 22 cards, matched to the WJEC A Level Maths (1300QS) 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.