remember

and FOIL, a way to remember to distribute
First
Outer
Inner
Last
that is an order to multiply the terms
so
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FOIL
First: 2x³ times 3x³=2 times x³ times 3 times x³=6x⁶
Outer: 2x³ times -2x²=-4x⁵
Inner: -x² times 3x³=-3x⁵
Last: -x² times -2x²=2x⁴
add them together
6x⁶-4x⁵-3x⁵+2x⁴=
6x⁶-7x⁵+2x⁴