2ˣ - 3 = 1
2ˣ = 1 + 3
2 ˣ = 4
2ˣ = 2² ==> x = 2
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3ˣ⁺¹ = 3 x 3ˣ
3ˣ x 3 = 3 x 3ˣ ==> ∀ x ∈N; R
6ˣ⁺⁸ = 36 x 6²ˣ
6ˣ⁺⁸ = 6²ˣ ⁺ ² ===> x + 8 = 2 x + 2 => 2 x - x = 8 - 2 => x = 6
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2ˣ ⁺⁷ = 2ˣ x 2ˣ⁺¹ = 2²ˣ ⁺¹ = > 2 x + 1 = x + 7 ==> 2 x - x = 7 - 1 => x = 6