Question

okay I have 4 but one at a time.... someone unstump me please.

1) Write the equation of the quadratic function with roots -1 and 1 and a vertex at (0, -3).

Answer 1

My brain gets jumbled too easy so keep it simple please

Answer 2

this one we do the vertex way
if the vertex is \((h,k)\) we know it looks like
\[y=a(x-h)^2+k\]
simple or no?

Answer 3

replace \(h\) by 0, \(k\) by -3 and write
\[y=a(x-0)^2-3\] i.e. \[y=ax^2-3\] the only number you do not know is \(a\)

Answer 4

meh... kinda. this has my mind completely lost :/

Answer 5

OHHH!

Answer 6

then take a break from it, there is no other way to do it, use the roots, or use the vertex

Answer 7

I cant. I need to finish it

Answer 8

please finish this one :)

Answer 9

Ill try the next one with your guidance

Answer 10

we know that
\[f(1)=0\] so to find \(a\) replace \(x\) by 1, set the result equal to zero,
you have
\[f(x)=ax^2-4\]
\[f(1)=a(1)^2-3=0\]
\[a-3=0\]
\[a=3\] answer is
\[f(x)=3x^2-3\]

Answer 11

typo on first line, should have been
\[f(x)=ax^2-3\]

Answer 12

I kind of get it (:

Answer 13

can we do the next one? Guide me?