Date | May 2021 | Marks available | 5 | Reference code | 21M.1.SL.TZ1.13 |
Level | Standard Level | Paper | Paper 1 | Time zone | Time zone 1 |
Command term | Find | Question number | 13 | Adapted from | N/A |
Question
Sieun hits golf balls into the air. Each time she hits a ball she records , the angle at which the ball is launched into the air, and , the horizontal distance, in metres, which the ball travels from the point of contact to the first time it lands. The diagram below represents this information.
Sieun analyses her results and concludes:
.
Determine whether the graph of against is increasing or decreasing at .
Sieun observes that when the angle is , the ball will travel a horizontal distance of .
Find an expression for the function .
Markscheme
(M1)
A1
the curve is decreasing at A1
Note: For the final A1, follow through within this question part for their value. Award A0 for an answer of "decreasing" with no work shown.
[3 marks]
recognition of need to integrate (e.g. reverse power rule or integral symbol or integrating at least one term correctly) (M1)
A1A1
(M1)
Note: Award M1 for correct substitution of and . A constant of integration must be seen (can be implied by a correct answer).
A1
Note: Accept any variable in the working, but for the final A1, the variable must be used in the expression.
[5 marks]