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sunstar2882
10-17-2011, 01:03 PM
For the function g(x)=2xcubed + 5xsquared - 28x - 15

a) Determine the maximum number of real zeros that the function may have.

b)Determine if (x-3) is a factor.

c)List the potential rational zeros.
?

d) Determine the real zeros of g
?

e) Find the x and y intercepts.
I answered y intercept= -15 and x intercepts= -5, 3

f) Determine if the graph touches or crosses the x-axis at the intercepts
?

g) Find the power function that the graph resembles for large values of absolute value x (end behavior).
?

Just wondering if I did the few I answered right and how to do the other ones. Thanks!

Subhotosh Khan
10-17-2011, 01:39 PM
For the function g(x)=2xcubed + 5xsquared - 28x - 15

a) Determine the maximum number of real zeros that the function may have.

b)Determine if (x-3) is a factor.

c)List the potential rational zeros.

±1, ±3, ±5, ±½, ±3/2, ±5/2

d) Determine the real zeros of g

g(x) = (x-3)(2x2 + 11x + 5) ... now use quadratic formula to find oter zeros

= 2(x-3)(x+5)(x+½)

e) Find the x and y intercepts.
I answered y intercept= -15 and x intercepts= -5, 3,-½

f) Determine if the graph touches or crosses the x-axis at the intercepts

There are no repeated roots - hence the graph crosses the x-axis at all the roots

g) Find the power function that the graph resembles for large values of absolute value x (end behavior).

y = 2x3

Just wondering if I did the few I answered right and how to do the other ones. Thanks!
.