Correct option is BGiven:x−1x=10x-\dfrac{1}{x}=10x−x1=10Find x3−1x3x^{3}-\dfrac{1}{x^{3}}x3−x31Solution:(x−1x)2=x2+1x2−2(x-\frac{1}{x})^{2}=x^{2}+\frac{1}{x^{2}}-2 (x−x1)2=x2+x21−2x2+1x2=102+2=102x^{2}+\frac{1}{x^{2}}=10^{2}+2=102x2+x21=102+2=102x3−1x3=(x−1x)(x2+1x2+1)=10(102+1)=10×103=1030x^{3}-\frac{1}{x^{3}}=(x-\frac{1}{x})\left(x^{2}+\frac{1}{x^{2}}+1\right)=10(102+1)=10\times 103=1030x3−x31=(x−x1)(x2+x21+1)=10(102+1)=10×103=1030