Math

posted by .

How do you factor 3x^3+81

• Math -

Call it 3(x^3 + 27).
27 is the cube of three, so one root is x = -3 and the corresponding factor is (x+3). For the other factor, use syntheic division to compute
(x^3+27)/(x+3). That turns out to be
(x^2 -3x + 9). The other roots are complex, so leave it as

3x^3 + 81 = 3(x+3)(x^2 -3x + 9)

Respond to this Question

 First Name School Subject Your Answer

Similar Questions

1. Math

Factor Completely: I am really confused on how to start it. 12q^5w^2-36q^4w^3-120q^3w^4 Help please. :) Factor out 12q^3w^2: 12q^3w^2(q^2 - 3qw - 10w^2) Can we factor further?
2. Factor

How do I factor these: 2x2 - 16x + 30 4x^2-9 x^2-5x 5x^2-26x+5 25x^2+4 Example: 2x^2 - 16x + 30 = 2 (x^2 - 8 x + 15) 2(x - 5)(x - 3) The first, factor out a 2 first. Then factor . The second...difference of two squares Third factor …
3. math

Is 3 a factor of 261? Is 10 a factor of 325?
4. math

If the sides of a box all double in length, by how much does its volume increase?
5. Math

Use the Factor Theorem to determine whether x-3 is a factor of P(x)=2x^3-5x^-9 . Specifically, evaluate P at the proper value, and then determine whether x-3 is a factor. P(_)=__ also pick which one applies x-3 is not a factor of P(x) …
6. stats

two factor ANOVA indep measures exper. 2 level factor A 3 level factor B n=5 in each treatment SS df ms between 240 5 factor A ?
7. MATH 101

Factor completely. Be sure to factor out the greatest common factor first if it is other than 1. (If the polynomial is prime, enter PRIME.) 56a^2+39ab-27b^2
8. math 1350

Find the three digit number that satisfies the following conditions: . Has a factor of 3. . Has a factor of 5. . Has a factor of 7. . All digits are prime. Describe the thinking process you went through to solve this problem.
9. science help

Two factors which cause global climate change are listed below. Factor 1: Volcanic eruptions. Factor 2: Changes in the amount of Sun’s heat received by the Earth’s atmosphere and surface. Which of these statements is correct about …
10. itc c++

can any one please dry run this code #include<iostream> using namespace std; int main() { intnum,factor=1,temp; cout<<"Enter any integer value"<<endl; cin>>num; //number given by the user is 10123. temp=num; …

More Similar Questions