Question

Sa se arate ca sunt cuburi a=2^24,b=4^9,c=8^10,d=27^5 ,e=225+225×2+225×3+....+225×80

Answer 1

a=2^(3*8)=(2^8)^3
b=4^(3*3)=(4^3)^3
c=(2^3)^10=(2^10)^3
d=(3^3)^5=(3^5)^3
e=225(1+2+3+...+80)=15^2*81*80/2=15^2*81*40=3^2*5^2*3^4*5*2^3=
2^3*3^6*5^3=(2*3^2*5)^3