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24 votes
24 votes
Find f such that f'(x) = 8x – 3. f(4) = 0​

User InBetween
by
2.6k points

2 Answers

17 votes
17 votes

Answer: y=29 / (4,29)

Explanation:

By graphing
f(x)=8x-3 and
f(4)=0 on Desmos. You'll be able to find that when x is 4, y is 29.

Similarly, you can plugin 4 into the original equation (
f(x)=8x-3) Which looks like:


8(4)-3\\32-3=29

Additionally, you can change
f(x)= to
y= as it is the exact same thing. With that in mind, you can do the same with
f(x)=0 and just change it to x=4. As you're wanting to know what the y-value is when x=4.

User Shadia
by
2.9k points
13 votes
13 votes

Answer:

4x²-3x+c is our original equation

Explanation:

we have an independent number I called this number c

put 4 from x and try to find c

f(4)=4*(4²)-3*(4)+c=0

we have to be careful about f(4) is 0

64-12+c=0 and c is -52 so our original equation is 4x²-3x-52

User Romy
by
2.5k points