👤

a).7 la puterea x+1-2*7 la puterea x=35 b).6 la puterea x+1-3*6 la puterea x=108

Răspuns :

a) 7^x+1 - 2 × 7^x = 35

7^x × 7 - 2 × 7^x = 35

7^x ( 7 - 2) = 35

7^x × 5 = 35

7^x = 35 : 5

7^x = 7^1

x = 1
_____


b) 6^x+1 - 3 × 6^x = 108

6^x × 6 - 3 × 6^x = 108

6^x ( 6 - 3) = 108

6^x × 3 = 108

6^x = 108 : 3

6^x = 36

6^x = 6^2

x = 2
______