In an under damped single degree of freedom system, the ratio of the first peak amplitude to the seventh peak amplitude is
\[
\frac{x_1}{x_7}=64.
\]
Then, the ratio of two successive peak amplitudes is
Show Hint
If
\[
\boxed{
\frac{x_1}{x_{n+1}}=R,
}
\]
then the ratio of two successive amplitudes is
\[
\boxed{
r=R^{1/n}.
}
\]