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    				| 1. | The distributive law from algebra states that for real numbers c, a1 and a2, we have c(a1 + a2) = ca1 + ca2 Use this law and mathematical induction to prove that, for all natural numbers, n ≥ 2, if c, a1, a2, …... an are any real numbers, then c(a1 + a2 +…+ an) = ca1 + ca2 +…+ can. | 
| Answer» Let P(n):c(a1+a2+…+an) = ca1+ca2+…+can ,for all natural numbers, n ≥ 2. Step1: For n=2, P(2) LHS= c(a1 + a2) RHS= c a1 + ca2 As, it is given that c(a1 + a2) = c a1 + ca2 Thus, P(2) is true. Step2: For n=k, Let P(k) be true So, c(a1+a2+…+ak ) = ca1+ca2+…+cak Now, we need to show P(k+1) is true whenever P(k) is true. P(k+1): LHS= c(a1+a2+…+aK+ak+1) =c[(a1+a2+…+aK)+ak+1] =c(a1+a2+…+aK)+cak+1 =ca1+ca2+…+caK+cak+1 = RHS Thus, P(k+1) is true, so by mathematical induction P(n) is true. | |