Mathematical Methods — Question 1

QCAA 2022, Paper 2 · 1 mark

Q1 · 2022 · Technology-activeSimple familiar1 mark

QUESTION 1

The position (in cm) of a particle is given by

x=\cos(4t)

, where

t

is time (in seconds). The velocity of the particle when

t=5

(A)

1.6323

cm s

^{-1}

(B)

0.4081

cm s

^{-1}

(C)

-0.9129

cm s

^{-1}

(D)

-3.6518

cm s

^{-1}

ABCD

WORKED SOLUTION

1 mark

ANSWER

D —

-3.6518

cm s

^{-1}

Worked solution

v=x'=-4\sin(4t)

, so

v(5)=-4\sin20\approx-3.6518

cm s

^{-1}

; D.

Selects option D.

[1 mark]

Worked explanation by QCE Vault; correct option verified against the QCAA answer key.