Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Can someone please help me with these factoring algebra problems? Please I m desperate to passing this exam?
I have an exam tomorrow, and still not sure how to solve these. I have practice questions with the answers, could you explain any of these step by step on how to get them?
Question 1: Factor x^3 +1
answer 1: (x+1)(x^2-x+1)
question 2: factor x^3 - 27
answer to 2: (x-3)(x^2+3x+9)
question 3: factor 4x^3 - 36x
answer to 3: 4x(x+3)(x-3)
question 4: factor 2x^3 - x^2 + 8x -4
answer to 4: (2x-1)(x^2+4)
1 Answer
- icemanLv 74 years ago
For 1 & 2 : The sum / difference of two cubes can be factored by using formulas:
(a³ + b³) = (a + b)(a² - ab + b²)
(a³ - b³) = (a - b)(a² + ab + b²)
3) 4x³ - 36x
= 4x(x² - 9) => use the difference of squares: (a² - b²) = (a - b)(a + b)
4) 2x³ - x² + 8x - 4 => factor by grouping:
= x²(2x - 1) + 4(2x - 1)
= (2x - 1)(x² + 4)
Good luck.