Question

Find a cubic function with the given zeros.
Square root of seven., -Square root of seven., -4

f(x) = x^3 + 4x^2+ 7x - 28
f(x) = x^3 + 4x^2 - 7x - 28
f(x) = x^3 - 4x^2 - 7x - 28
f(x) = x^3 + 4x^2 - 7x + 28

Answer 1

\[f(x)=\left( x-\sqrt{7} \right)\left( x+\sqrt{7} \right)\left( x+4 \right)\]
simplify it.

Answer 2

@ganeshie8 @jim_thompson5910 @sweetburger @mathstudent55 @sammixboo

Answer 3

@hartnn

Answer 4

PLEASE HELP, I AM RUNNING OUT OF TIME TO FINISH

Answer 5

@jim_thompson5910

Answer 6

@ganeshie8

Answer 7

as @sshayer wrote out, expand that polynomial out to get...

\[\Large f(x) = (x-\sqrt{7})(x+\sqrt{7})(x+4)\]
\[\Large f(x) = (x^2-(\sqrt{7})^2)(x+4)\]
\[\Large f(x) = (x^2-7)(x+4)\]
\[\Large f(x) = x^2(x+4)-7(x+4)\]

I'll let you finish up

Answer 8

f(x)=x^3+4x^2-7x-28 ???

Answer 9

yes that's right

Answer 10

that's the answer

Answer 11

I agree

Answer 12

ik because i used mathway, an online calculator u should check it out it helps a lot

Answer 13

Thanks :)