a = 4, d = 0

(iii) a = 4, d = 0 (1 mark)

Sol. a = 4, d = 0

Here, t1 = a = 4

t2 = t1 + d = 4 + 0 = 4

t3 = t2 + d = 4 + 0 = 4

t4 = t3 + d = 4 + 0 = 4

t5 = t4 + d = 4 + 0 = 4

∴  The first five terms of the A.P. are 4, 4, 4, 4 and 4.