plz solve this question
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given equation : 8×2²ˣ + 4 × 2ˣ⁺¹ = 1 + 2ˣ
=> 8 × 2²ˣ + 4 x 2ˣ x 2¹ = 1 + 2ˣ
=> 8 x 2²ˣ + 8 x 2ˣ = 1 + 2ˣ
let a = 2ˣ
the equation reduces to
8a² + 8a = 1 + a
=> 8a² + 8a - a - 1 = 0
=> 8a² + 7a - 1 = 0
=> 8a² + 8a - a - 1 = 0
=> 8a (a + 1) - 1 (a + 1) = 0
=> (8a - 1)(a + 1) = 0
=> 8a - 1 = 0 or a = 1/8
=> a + 1 = 0 or a = -1
when a = 1/8
1/8 = 2ˣ => 1/2³ = 2ˣ => 2⁻³ = 2ˣ
=> - 3 = x => x = - 3
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