MediumPower & Taylor series

Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) §10.5 Power Series, #30 · Calculus · Power & Taylor series

(a) What is the coefficient of … when … multiplies

(a) What is the coefficient of $x^{n}$ when $1 + x + x^{2} + \dots$ multiplies $1 + x + x^{2} + \dots$ ? Write the first three terms.
(b) What is the coefficient of $x^{5}$ in $(Σ x^{k})^{3}$ ?

~8 minWritten answer · check your work with Lemma

Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) · §10.5 Power Series, #30

Stuck? A gentle nudge

No hints for this one.

Something off?

Workspace

Your working

Check your full solution

Upload photos of your handwritten work or a PDF, and Lemma will read it and tell you whether it's right — and where it first goes wrong if not.