Practice for lesson 9 of 18, 9 problems
Practice: Cubing a binomial and squaring a trinomial
Practice problems with solutions on cubing a binomial and squaring a trinomial: expansions with coefficients and signs, simplifying, and a cube volume problem.
Review the lessonWork each problem out on paper before you open the solution. If your answer is off, compare the steps and find where you went wrong. If a problem stops you cold, go back to the lesson: every set links to it.
Warm-up
Level up
Word problems
Quick check
Practice 8Quick check
What is the coefficient of \(x\) in \((x - 2)^3\)?
The third term is \(3 \cdot x \cdot (-2)^2 = 12x\).
Practice 9Quick check
What is the sum of the coefficients of \((x + 1)^3\) once it's expanded?
\(x^3 + 3x^2 + 3x + 1\): \(1 + 3 + 3 + 1 = 8\). (Shortcut: plug in \(x = 1\) to get \(2^3\).)
All done?
If you got most of them right, you're ready to move on. If not, reread the lesson and try the ones you missed again in a few days.