Question

Aflati l pe x
Doar d. e.

Answer 1

d)  4ˣ + 4ˣ⁺¹ + 4 ˣ ⁺ ²  = 336

4ˣ x ( 1 + 4 + 4² ) = 336

4ˣ x 21 = 336

4ˣ = 336 : 21

4ˣ = 16

4ˣ = 4² ⇒   x = 2

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e)2²ˣ ⁺ ¹ + 2²ˣ ⁺ ³ + 2²⁽ ˣ ⁺ ¹ ⁾ = 896

2²ˣ x ( 2¹ + 2³ + 2² ) = 896

2²ˣ  x 14 = 896

2 ²ˣ = 896 : 14

2²ˣ  = 64

2²ˣ = 2⁶ ⇒   2 x = 6 ⇒  x = 6 : 2 ⇒ x = 3