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Further applications of differentiation — Question 13

Original QCE Vault practice · 1 mark

Q13 · Practice questionTechnology-freeSimple familiar1 mark

QUESTION 13

The stationary points of

f(x)=x^3-3x^2-9x+4

occur when

x=

(A)

-3,1

(B)

-1,1

(C)

-1,3

(D)

1,3

ABCD

Question linkSyllabus coverage

WORKED SOLUTION

Answer C

1 mark

ANSWER

C

Worked solution

f'(x)=3x^2-6x-9=3(x+1)(x-3)

, so

x=-1,3

.

Selects the correct option.

[1 mark]

Practice question aligned to the current QCAA syllabus; review the worked solution and marking criteria.

View the QCAA syllabus

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