Question 6
What is the coefficient of $x^2$ in the product $(1-x)(1+2x)(1-2^2x)(1+2^3x)(1-2^4x)(1+2^5x)(1-2^6x)(1+2^7x)$?
IMAS 2022–2023 — Junior Division — Round 2 Question 6
IMAS · IMAS 2022–2023 — Junior Division — Round 2
IMAS · IMAS 2022–2023 — Junior Division — Round 2