1. Упростите выражение: a) $$3a^2b \cdot (-5a^4b)$$; б) $$(x - 2)^2 - 2x(3 - 2x)$$.

a) $$3a^2b \cdot (-5a^4b) = 3 \cdot (-5) \cdot a^2 \cdot a^4 \cdot b \cdot b = -15a^{2+4}b^{1+1} = \textbf{-15a^6b^2}$$. б) $$(x - 2)^2 - 2x(3 - 2x) = (x^2 - 4x + 4) - (6x - 4x^2) = x^2 - 4x + 4 - 6x + 4x^2 = x^2 + 4x^2 - 4x - 6x + 4 = 5x^2 - 10x + 4 = \textbf{5x^2 - 10x + 4}$$.