1.Let C1,C2,C3,…C_1, C_2, C_3, \ldotsC1,C2,C3,… be the usual binomial coefficients where Cr=nCrC_r = {}^nC_rCr=nCr. Let S=C1+2C2+3C3+…+nCnS = C_1 + 2C_2 + 3C_3 + \ldots + nC_nS=C1+2C2+3C3+…+nCn, then SSS is equal toa.n⋅2nn \cdot 2^nn⋅2nb.2n−12^{n-1}2n−1c.n⋅2n−1n \cdot 2^{n-1}n⋅2n−1d.2n+12^{n+1}2n+1Login to continueOnly logged in users canattempt or see the solution.
