证明恒等式 $\dfrac{C_n^0}{2^n}+\dfrac{C_{n+1}^0}{2^{n+1}}+\dfrac{C_{n+2}^0}{2^{n+2}}+\cdots+\dfrac{C_{2n}^0}{2^{2n}}=1.$
证明恒等式
\[
\dfrac{C_n^0}{2^n}+\dfrac{C_{n+1}^0}{2^{n+1}}+\dfrac{C_{n+2}^0}{2^{n+2}}+\cdots+\dfrac{C_{2n}^0}{2^{2n}}=1.
\]
证明恒等式
\[
\dfrac{C_n^0}{2^n}+\dfrac{C_{n+1}^0}{2^{n+1}}+\dfrac{C_{n+2}^0}{2^{n+2}}+\cdots+\dfrac{C_{2n}^0}{2^{2n}}=1.
\]