(2a+3b)(4a+5b)(2a-3b)(4a-5b)
=(4a^2-9b^2)(16a^2-25b^2)
=16a^2-244a^2b^2+225b^2
(Y-3)的二次方-2(y+2)(y-2)
=Y^2-6Y+9-2y^2+8
=y^2-8y+17