Expand (3x - 2)^3: animated lesson
A narrated, step-by-step expanding and factoring video lesson with captions. Final answer: 27x^3 - 54x^2 + 36x - 8.
Video with a synthetic English voice and captions. Pick another language for subtitles in that language, or open the interactive version.
Video narrated by a synthetic voice (Piper TTS, en_US-ljspeech-high voice (LJ Speech dataset, public domain)); the steps come from our maths engine and the answer was checked independently. Download MP4 (0.3 MB) · Captions (WebVTT)
Steps on screen
- 1. The problemWorked example
- 2. Step by step
- Distribute every product and power
- Combine like terms and order by degree
- Read off the key features
- 3. The answer
(3x - 2)^3 = 27x^3 - 54x^2 + 36x - 8
- 4. Check
- Spot check at x = 2: original and expanded form both give 64.
Transcript
The problem. Here is the problem: (3x minus 2) cubed. Expand and simplify the polynomial into standard form.
Step by step. Distribute every product and power. Multiply each term of one factor by each term of the other; expand powers by repeated multiplication. Combine like terms and order by degree. Read off the key features. degree 3, leading coefficient 27, constant term negative 8.
The answer. So the answer is 27x cubed minus 54x squared plus 36x minus 8. In standard form the polynomial is 27x cubed minus 54x squared plus 36x minus 8 (degree 3, leading coefficient 27, constant term negative 8).
Check. Spot check at x equals 2: original and expanded form both give 64.
About expanding and factoring
Expand products of brackets and factor polynomials completely.
More lessons like this
- Video lesson0:38AlgebraHigh school3 stepsFactor x² - 2
Expanding and factoring
- Video lesson0:49AlgebraHigh school4 stepsFactor x² + 5x - 6
Expanding and factoring
- Video lesson0:43AlgebraHigh school3 stepsExpand (5x + 2)(3x - 3)
Expanding and factoring
- Video lesson0:28AlgebraHigh school3 stepsFactor x² + 7x
Expanding and factoring
- Video lesson0:43AlgebraHigh school3 stepsExpand (3x - 5)² - (3x + 6)
Expanding and factoring
- Video lesson0:46AlgebraHigh school4 stepsFactor x² + 5x + 6
Expanding and factoring