(1/3)50. (-9)25 - 2/3 : 4
= (1/3)50 . [(-3)2]25 - 2/3 . 1/4
= (1/3)50.(-3)50- 1/6
= (1/3 . -3 )50 - 1/6
= (-1)50- 1/6
= 1 - 1/6
= 5/6
theo đề ta có
=\(\left(\frac{1}{3^{ }}\right)^{50}.\left(-9\right)^{25}-\frac{2}{3}.\frac{1}{4}\)
=\(\left(\frac{1}{3}\right)^{50}.\left(\frac{1}{3}\right)^{25}.\left(-27\right)^{25}-\frac{1}{6}\)
=\(\left(\frac{1}{3}\right)^{50+25}.\)