1) (-6a+2b)²=4b²-24ab+36a²2) (-3x-8y)²=9x²+48xy+64y²3) (-0.7m-10n²)²=0.49m+14mn²+100n⁴4) (-4a³+1/2b⁴)²=1/4b^6-4a³b⁴+16a^5