b) (1/2)^3 . 4 + 3/4

= 1/8 . 4 + 3/4

= 1/2 + 3/4

= 5/4

c) 4^3 : 2^5 + 3^5

= 64 : 32 + 243

=2 + 243

=245

d) (27^10 + 9^5)/(9^13 + 27^2)

={(3^3)^10+(3^2)^5}/{(3^2)^13+(3^3)^2}

={3^30+3^10}/{3^26+3^6}

={3^10 . (3^20+1)}/{3^6 . (3^20+1)}

={3^10}/{3^6}

=3^4

=81

@kaff

Giải thích các bước giải:

b) (1/2)^3 . 4 + 3/4

= 1/8 . 4 + 3/4

= 1/2 + 3/4

= 2/4 + 3/4

= 5/4

-----

c) 4^3 : 2^5 + 3^5

= 64 : 32 + 243

= 2 + 243

= 245

-----

d) (27^10 + 9^5 )/(9^13 + 27^2)

= ((3^3)^10 + (3^2)^5)/((3^2)^13 + (3^3)^3)

= (3^30 + 3^10)/(3^26 + 3^9)

= (3^10. (3^20 + 1 ))/( 3^6 . (3^20 + 1 ))

= 3^10 : 3^6

= 3^(10 - 6)

= 3^4

= 81

#By