益阳中心医院招聘官网:设A=1+2x*x*x*x,b=2x*x*x+x*x,x为实数不等于1,比较A,B大小

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要求有具体过程

A=1+2x×x×x×x=2X^4+1
B=2x×x×x+x×x=2X^3+X^2
A-B=2X^4+1-(2X^3+X^2)
=2X^4-2X^3-X^2+1
=2X^3(X-1)-(X-1)(X+1)
=(X-1)(2X^3-X-1)
=(X-1)(X-1)(2X^2+2X+1)
=(X-1)^2×[X^2+(X+1)^2]
而x为实数不等于1,所以(X-1)^2>0,X^2+(X+1)^2>0
即A-B>0
故A>B

A=1+2x*x*x*x=2X^4+1
B=2x*x*x+x*x=2X^3+X^2
A-B=2X^4+1-(2X^3+X^2)
=2X^4-2X^3-X^2+1
=2X^3(X-1)-(X-1)(X+1)
=(X-1)(2X^3-X-1)
=(X-1)(X-1)(2X^2+2X+1)
=(X-1)^2*[X^2+(X+1)^2]
因为x为实数不等于1,所以A-B>0
A>B