a. \(3x^2-2x\left(5+1.5x\right)+10\)
\(=3x^2-10x-3x^2+10\)
\(=-10x+10\)
b. \(\left(x^2-2x+3\right)\left(x-4\right)\)
\(=x^3-2x^2+3x-4x^2+8x-12\)
\(=x^3-6x^2+11x-12\)
c. \(\left(5x+2\right)\left(2x^2-3x-1\right)\)
\(=10x^3-15x^2-5x+4x^2-6x-2\)
\(=10x^3-11x^2-11x-2\)
d. \(\left(25x^2+10xy+4y^2\right)\left(5x+2y\right)\)
\(=125x^3+50x^2y+20xy^2+50x^2y+10xy^2+6y^3\)
\(=125x^3+100x^2y+30xy^2+6y^3\)
e. \(\left(5x^3-x^2+2x-3\right)\left(4x^2-x+2\right)\)
\(=20x^5-4x^4+2x-12x^2-5x^4+x^3-2x^2+3x+10x^3-2x^2+4x-1\)
\(=20x^5-9x^4+9x-16x^2+11x^3+1\)