用适当方法解(x+3)=(1-2x)²
问题描述:
用适当方法解(x+3)=(1-2x)²
答
x+3=1-4x+4x²4x²-5x=2x²-5x/2=1/2x²-5x/2+25/16=1/2+25/16(x-5/4)²=33/16x-5/4=±√33/4∴x=5/4±√33/4即x1=(5-√33)/4,x2=(5+√33)/4
用适当方法解(x+3)=(1-2x)²
x+3=1-4x+4x²4x²-5x=2x²-5x/2=1/2x²-5x/2+25/16=1/2+25/16(x-5/4)²=33/16x-5/4=±√33/4∴x=5/4±√33/4即x1=(5-√33)/4,x2=(5+√33)/4