Solve {l}{P=1/2^{n-1}-2^{n},Q=2/2^{n+2+2}B}{R=[a-{a^{-1}+(b^-1-a)^-1}^-1]+a^2b}

$$\left. \begin{array} { l } { P = \frac { 1 } { 2 ^ { n } - 1 } - 2 ^ { n } , Q = \frac { 2 } { 2 ^ { n + 2 } + 2 } B } \\ { R = [ a - \{ a ^ { - 1 } + ( b ^ { - 1 } - a ) ^ { - 1 } \} ^ { - 1 } ] + a ^ { 2 } b } \end{array} \right.$$

Solve for P, n, Q, B, R, a, b

$$P=\frac{2^{n}-4^{n}+1}{2^{n}-1}$$

$$n\in \mathrm{R}$$

$$Q=\frac{B}{2^{n+1}+1}$$

$$B\in \mathrm{R}$$

$$R=2ba^{2}$$

$$a\in \mathrm{R}$$

$$b\in \mathrm{R}$$