Khan Academy (English - US curriculum)
Math by grade
Eureka Math/EngageNY
Algebra 2 (Eureka Math/EngageNY)
Module 1: Polynomial, rational, and radical relationships
Topic D: Lessons 38-40: Complex roots and the fundamental theorem of algebra
Factoring sum of squares
Factoring sum of squares
Sal factors 36a^8+2b^6 as (6a^4-i*√2b^3)(6a^4+i*√2b^3).
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