a) ( 4/9 : 2/3 + 4 2/3 ) × 9/40 =
= ( 4/9 × 3/2 + 14/3 ) × 9/40 =
= ( 2/3 + 14/3 )× 9/40 =
= 16/3 × 9/40 =
= 2 × 3/5 = 6/5
b) (7/5)^4 × ( 7/5)^5 × (7/5)^6 : (( 7/5 )^3)^5 =
Simplifici inmultind exponentii
= ( 7/5)^4 × (7/5)^5 × (7/5)^6 : (7/5)^15 =
Imparirea cu a^n inseamna inmultirea cu a^-n
= ( 7/5)^4 × (7/5)^5 × (7/5)^6 : (7/5)^-15 =
Daca au aceeasi baza inmultesti puterile
= (7/5)^4+5+6-15 =
= (7/5)^0 = 1 deoarece orice expresie nenula ridicara la puterea 0 da 1.
