Which of the following numbers will completely divide $$7^{81} + 7^{82} + 7^{83}$$ ?
$$7^{81} + 7^{82} + 7^{83}$$ =Â $$7^{80}\left(7+7^2+7^3\right)$$
=Â $$7^{80}\left(7+49+343\right)$$
=Â $$7^{80}\left(399\right)$$
=Â $$399\left(7^{80}\right)$$
$$\therefore\ $$399 completely divides the $$7^{81} + 7^{82} + 7^{83}$$
Hence, the correct answer is Option B
Create a FREE account and get:
