①-10又3/8*9又5/8 ②解方程4(x-3)(x-1)-(2x-3)^2-6=0 ③已知(a+2b)^2=7,(a-2b)^2=3,求a^2+4b^2

问题描述:

①-10又3/8*9又5/8 ②解方程4(x-3)(x-1)-(2x-3)^2-6=0 ③已知(a+2b)^2=7,(a-2b)^2=3,求a^2+4b^2
及ab得值

③a^2+4b^2=5,ab=1/2