Practicing Success
If $s − \frac{1}{s−8} =20$, then the value of $(s − 8)^3 −\frac{1}{(s−8)^3}$ is: |
1324 1764 1864 1944 |
1764 |
If x - \(\frac{1}{x}\) = n then, $x^3 - \frac{1}{x^3}$ = n3 + 3 × n If $s − \frac{1}{s−8} =20$ then the value of $(s − 8)^3 −\frac{1}{(s−8)^3}$ = ? Subtract 8 from both sides, $s - 8 − \frac{1}{s−8} =20 - 8$ $s - 8 − \frac{1}{s−8} =12$ Then, $(s − 8)^3 −\frac{1}{(s−8)^3}$ = 123 + 3 × 12 = $(s − 8)^3 −\frac{1}{(s−8)^3}$ = 1728 + 36 = 1764 |