Prove the following by using the principle of mathematical induction for all
a + (a + d) + (a + 2d) + ...........+ [a + (n - 1)d] =
Prove the following by using the principle of mathematical induction for all
n (n + 1) (n + 5) is a multiple of 3.
Prove the following by using the principle of mathematical induction for all is a multiple of 27 for all
Let P(n): is a multiple of 27.
I.      For n = 1,
       P(1): is a multiple of 27
  41 - 14 is a multiple of 27
27 is a multiple of 27
        which is true.
∴      P(n) is true for n = 1
II.   Suppose P(n) is true for n = m,   P(m) :
is a multiple of 27
 ...(i)
III.  For n = m + 1,
       P (m + 1) : is a multiple of 27
       But,
          Â
          =       [By (i)]
           where
is a multiple of 27
∴          P(m + 1) is true.
∴          P(m) is true P(m + 1) is true.
Hence, by induction, P(n) is true for all
     Â
Prove the following by using the principle of mathematical induction for all is divisible by 11.
Prove the following by using the principle of mathematical induction for all is divisible by 8.
Prove by mathematical induction that sum of cubes of three consecutive natural numbers is divisible by 9.