Q3 of 153 Page 13

Find the value of following expression:

i49 + i68 + i89 + i110

i49 + i68 + i89 + i110 = i(48 + 1) + i68 + i(88 + 1) + i(108 + 2)


= (i4)12 × i + (i4)17 + (i4)11 × i + (i4)27 × i2


= i + 1 + i – 1 = 2i


[since i4 = 1, i2 = – 1]


i49 + i68 + i89 + i110 = 2i


More from this chapter

All 153 →
1

Evaluate the following:

(i) i457


(ii) i528


(iii)


(iv)


(v)


(vi) (i77 + i70 + i87 + i414 )3


(vii) (vii) i30 + i40 + i60


(viii) i49 + i68 + i89 + i118

 2

Show that 1 + i10 + i20 + i30 is a real number ?

 3

Find the value of following expression:

i30 + i80 + i120

 3

Find the value of following expression:

i + i2 + i3 + i4