[(x-2y)^2+(x-2y)(x+2y)-2x(2x-y)]/2x
=[x^2-4xy+4y^2+x^2-4y^2-4x^2+2xy]/2x
=[-2x^2-2xy]/2x
=-x-y
[(ab+10)(ab-2)-2a^2b^2+2]/(-ab)
=[a^2b^2+8ab-20-2a^2b^2+2]/(-ab)
=[8ab-a^2b^2-18]/(-ab)
=-8+ab+18/ab
=-8+3/2*(-4/3)+18/[3/2*(-4/3)]
=-19
[(x-2y)^2+(x-2y)(x+2y)-2x(2x-y)]/2x
=[x^2-4xy+4y^2+x^2-4y^2-4x^2+2xy]/2x
=[-2x^2-2xy]/2x
=-x-y
[(ab+10)(ab-2)-2a^2b^2+2]/(-ab)
=[a^2b^2+8ab-20-2a^2b^2+2]/(-ab)
=[8ab-a^2b^2-18]/(-ab)
=-8+ab+18/ab
=-8+3/2*(-4/3)+18/[3/2*(-4/3)]
=-19