Binomial Theorem
Multinomial Expansion
Premium Question
Grade 11

Question:

The number of terms in the expansion of $(1 + 2x + x^2)^{10}$ is:
(1) $11$
(2) $20$
(3) $21$
(4) $22$

Step-by-Step Solution

Key Concept: Notice that the expression inside the brackets is a perfect square — rewrite $1 + 2x + x^2$ as $(1 + x)^2$ and simplify the whole expression to a single binomial power before counting its terms.
The detailed step-by-step mathematical proof is available inside the Mathbee app workspace.
Correct Answer: (3)

Master Binomial Theorem with Mathbee

Practice this topic under real exam conditions with strict timers, or ask our AI Mentor to explain the concepts step-by-step.

Start Practicing for Free