Question

pls help ca nu ii dau de cap

Answer 1

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.