Mathematical Methods — Question 3

QCAA 2020, Paper 2 · 1 mark

Q3 · 2020 · Technology-activeSimple familiar1 mark

QUESTION 3

Let

R

be the region enclosed by the graph of

y=xe^x

, the

x

-axis, and the lines

x=-1

and

x=1

. The area of

R

is closest to

(A)

0.74

(B)

1.26

(C)

2.35

(D)

3.09

ABCD

WORKED SOLUTION

1 mark

ANSWER

Worked solution

Since

xe^x<0

[-1,0)

, the area is

-\int_{-1}^0xe^x dx+\int_0^1xe^x dx\approx0.2642+1=1.2642

. Hence B.

Selects option B.

[1 mark]

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