Question 475560
{{{ P(x) = x^3+4x^2-x-4 }}}
Factor this by grouping
P(x) = x^3 - x + 4x^2 - 4
P(x) = (x^3 - x) + (4x^2 - 4)
factor
P(x) = x(x^2 - 1) + 4(x^2 - 1)
Factor out (x^2-1)
P(x) = (x^2 - 1)(x + 4)
x^2 = 1
x = {{{sqrt(1)}}}
x = 1
x = -1
and
x = -4
:
x intercepts: -4, -1, +1
:
Find the y intercept, occurs when x=0
y = x^3 + 4x^2 - x - 4 
y = 0^3 + 4(0)^2 - 0 - 4
y = -4 is the y intercept
:
:
graphically
{{{ graph( 300, 200, -6, 6, -10, 10, x^3+4x^2-x-4  ) }}}