问题标题:
倒数法求值,已知x/x^-x+1=5,求x^/x的四次方+x^+1的值?
问题描述:
倒数法求值,
已知x/x^-x+1=5,求x^/x的四次方+x^+1的值?
况夯回答:
因为x/(x^2-x+1)=5,所以(x^2-x+1)/x=1/5,即x-1+1/x=1/5,x+1/x=6/5,故(x+1/x)^2=36/25,即x^2+2+1/x^2=36/25,所以x^2+1/x^2=36/25-2=-14/25,因此x^2+1+1/x^2=1-14/25=11/25,即(x^4+x^2+...
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