Question

Efectuatii, va rog.
Dau ciroana.

Answer 1

b)5^21-5^21=0

d)7^56-7^54=7^2

coroana altfel ma supar .

Answer 2

${5}^{20} \times 5 - {5}^{21} = {5}^{21} - {5}^{21} = 0 \\ \\ ( {7}^{8})^{7} \div {7}^{54} = {7}^{56} \div {7}^{54} = {7}^{2} = 49$