Question

帮我检查一下计算题对不对、有更好的方法吗

Answer 1

(1).3-(x+1)²=1

(x+1)²=3-1

(x+1)²=2

x+1=±√2

x=-1±√2

x1=-1+√2

x2=-1-√2

(2).2x²-3x-4=0

x²-3x/2=2

x²-3/2x+(3/4)²=2+(3/4)²

(x-3/4)²=41/16

x-3/4=±√41/4

x=3/4±√41/4

(3).3x²-6x-2=0

x²-2x=2/3

x²-2x+1=2/3+1

(x-1)²=5/3

x-1=±√15/3

x=1±√15/3

(4).x(x+1)+2(x-1)=0

x²+3x=2

x²+3x+(3/2)²=2+(3/2)²

(x+3/2)²=17/4

x+3/2=±√17/2

x=-3/2±√17/2