Question
Factor: f(x)=2x^4-5x^3-30x^2+80x-32 a) f(x)=(2x-1)(x-2)(x+4)(x-4) b) f(x)=(2x-1)(x-2)(x-4)^2 c) f(x)=(2x+1)(x-2)(x-4)^2 d) f(x)=(2x+1)(x+2)(x-4)^2
Solution
4.6
(245 Votes)
Sofia
Veteran ยท Tutor for 9 years
Answer
### a)
Explanation
## Step 1: Rational Root Theorem### The Rational Root Theorem helps identify potential rational roots of a polynomial. In this case, potential rational roots are of the form
, where
is a factor of the constant term (-32) and
is a factor of the leading coefficient (2). Possible rational roots are
.## Step 2: Testing Potential Roots### Substitute the potential roots into the polynomial
. We find that
. Therefore,
is a root, and
is a factor.## Step 3: Polynomial Division### Divide
by
using synthetic division or polynomial long division. This yields
.## Step 4: Factoring the Cubic### Now we factor the cubic
. Testing potential roots again, we find that
is a root since
. Thus,
is a factor.## Step 5: Further Polynomial Division### Dividing
by
gives
.## Step 6: Difference of Squares###
is a difference of squares, factoring to
.## Step 7: Final Factorization### Combining all factors, we have
.