Răspuns :
4ⁿ + 4ⁿ⁺¹ = 20
4ⁿ devine factor comun: 4ⁿ · (1 + 4) =20
4ⁿ · 5 = 20
4ⁿ = 20/5
4ⁿ = 4 → n = 1.
4ⁿ devine factor comun: 4ⁿ · (1 + 4) =20
4ⁿ · 5 = 20
4ⁿ = 20/5
4ⁿ = 4 → n = 1.
4ⁿ + 4ⁿ⁺¹ = 20
4ⁿ⁺⁰ + 4ⁿ⁺¹ = 20
4ⁿ· 4⁰ + 4ⁿ· 4¹ = 20
4ⁿ· ( 4⁰ + 4¹) = 20
4ⁿ ( 1+ 4) = 20
4ⁿ· 5 = 20
4ⁿ = 20: 5
4ⁿ = 4
4ⁿ = 4¹
n= 1
4ⁿ⁺⁰ + 4ⁿ⁺¹ = 20
4ⁿ· 4⁰ + 4ⁿ· 4¹ = 20
4ⁿ· ( 4⁰ + 4¹) = 20
4ⁿ ( 1+ 4) = 20
4ⁿ· 5 = 20
4ⁿ = 20: 5
4ⁿ = 4
4ⁿ = 4¹
n= 1