A curve with equation $y = f(x)$ passes through the point (2, 10) - Edexcel - A-Level Maths Pure - Question 9 - 2012 - Paper 1
Question 9
A curve with equation $y = f(x)$ passes through the point (2, 10). Given that
$f'(x) = 3x^2 - 3x + 5$
find the value of $f(0)$.
(5)
Worked Solution & Example Answer:A curve with equation $y = f(x)$ passes through the point (2, 10) - Edexcel - A-Level Maths Pure - Question 9 - 2012 - Paper 1
Step 1
Find the integral of $f'(x)$
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Answer
To find f(x), we need to integrate f′(x).
f(x)=∫(3x2−3x+5)dx
Calculating the integral, we have:
f(x)=x3−23x2+5x+c
where c is the constant of integration.
Step 2
Use the point (2, 10)
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Answer
We know the curve passes through the point (2, 10). This gives us:
f(2)=23−23(22)+5(2)+c=10
Simplifying this:
10=8−6+10+c
\
Which leads to: 10=12+c c=−2
Step 3
Find the value of $f(0)$
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Answer
Now, substituting c=−2 back into the equation for f(x), we have: