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Solve (2^2x+1)-9(2^x)+4=0​

User Buu
by
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1 Answer

7 votes
  • Answer:

x₁ = - 1

x₂ = 2

  • Explanation:

2²ˣ⁺¹ - 9ₓ2ˣ + 4 = 0

2²ˣₓ2 - 9ₓ2ˣ + 4 = 0

2ˣ = n

2n² - 9n + 4 = 0

2n² - n - 8n + 4 = 0

n(2n - 1) - 4(2n - 1) = 0

(2n - 1)(n -4) = 0

2n - 1 = 0 => n₁ = 1/2

n - 4 = 0 => n₂ = 4

2ˣ = 1/2 => 2ˣ = 2⁻¹ => x₁ = - 1

2ˣ = 4 => 2ˣ = 2² => x₂ = 2

User Morendo
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