解方程(x-1)눀=6;x눀-2x-1=0;2x눀-10x=3

2025-03-01 10:16:02
推荐回答(2个)
回答1:

解:(x-1)²=6
x-1=±√6
∴x-1=√6 x-1=-√6
x1=1+√6, x2=1-√6
解:x²-2x-1=0
x²-2x=1
(x-1)²=2
x-1=±√2
∴x-1=√2 x-1=-√2
x1=1+√2, x2=1-√2
解:2x²-10x=3
2x²-10x-3=0
x=(-(-10)±√((-10)²-4×2×(-3)))/2
x=(10±√124)/2
x=(10±2√31)/2
∴x1=(10+2√31)/2=5+√31,x2=(10-2√31)/2=5-√31

回答2:

①(x-1)²=6
x-1=±√6
x=1+√6或x=1-√6
②x²-2x-1=0
(x-1)²=2
x-1=±√2
x=1±√2
③2x²-10x=3
x²-5x=3/2
(x-5/2)²=3/2+25/4
(x-5/2)²=31/4
x-5/2=±(√31)/2
x=(5±√31)/2