Question

ME AJUDEM PFVR

RESOLVA AS EQUAÇÕES IRRACIONAIS
URGENTE

Answer 1

a) √x + 1 = 7
     (√x + 1)² = 7²
     x + 1 = 49
     x = 49 -1
     x = 48
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b) √7+x = 3
     (√7 + x)² = 3²
      7 + x = 9
      x = 9 - 7[
      x = 2
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c) √2x - 4 = 6
     (√2x - 4)² = 6²
      2x - 4 = 36
      2x = 36 + 4
      2x = 40
        x = 40 : 2
        x = 20
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d) √2x + 5 - 1 = 0
     √2x + 5 = 1
     (√2x + 5)² = 1²
     2x + 5 = 1
     2x = 1 - 5
    2x = -4
    x = -4 : 2
    x = -2
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e) √x + 1 - 2 = 0
     √x + 1 = 2
      (√x +1)² = 2²
      x + 1 = 4
     x = 4 - 1
     x = 3
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f) 2 + √x + 4 = 5
      √x + 4 = 5 - 2
       (√x + 4)² = 3²
       x + 4 = 9
      x = 9-4
    x = 5
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g) √3 + x = √9 - x
     (√3 + x)² = (√9 -x)²
      3 + x = 9 - x
      x + x = 9 - 3
      2x = 6
      x = 6:2
    x = 3 
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h) √5x - 10 = √8 + 3x
     (√5x - 10)² = (√8 + 3x)²
     5x - 10 = 8 + 3x
     5x - 3x = 8 + 10
      2x = 18
      x = 18 : 2
     x = 9
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i) √x = 2 - x
    (√x)² = (2-x)²
      x = 4 - 4x + x²
      x² - 4x - x + 4 = 0
      x²  - 5x + 4 = 0
      Δ= 25 - 4.1.4
      Δ = 25 - 16
      Δ = 9
     x' = 8/2 = 4
     x'' = 2/2 = 1
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j)  x = √6x - 8
    x² = (√6x-8)²
    x² = 6x - 8
    x² - 6x + 8 = 0
    Δ = 36 - 4.1.8
    Δ = 36 - 32
    Δ = 4
    x' = 8/2 = 4
    x'' = 4/2 = 2
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l)√x² + 3x - 2 = 0
   √x² + 3x = 2
    (√x²+ 3x )² = 2²
     x² + 3x = 4
     x² + 3x - 4 = 0
     Δ = 9 - 4.1 (-4)
    Δ = 9 + 16
    Δ = 25
   x' = 2/2 = 1
   x'= -8/2 = -4
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m) 2x = √9x - 2
     (2x)²= (√9x -2)²
      4x² = 9x - 2
      4x² - 9x + 2 = 0
      Δ = 81 - 4.4.2
     Δ = 81 - 32
     Δ = 49
    x' = 16/8 = 2
    x''= 2/8 = 1/4
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n) √x - 3 = x - 5
     (√x - 3)² = (x-5)²
      x - 3 = x² - 10x + 25
      x² - 10x - x + 25 + 3 = 0
      x² -11x +28 = 0
      Δ = 121 - 4.1.28
      Δ = 121 - 112
      Δ = 9
      x' = 14/2 = 7
      x'' = 8/2 = 4
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o) √x + x = 2
    √x = 2 - x
    (√x)² = (2-x)²
     x = 2² - 4x + x²
     x² -4x -x + 4 = 0
     x² -5x + 4 = 0
     Δ = 25 - 4.1.4
     Δ = 25 - 16
     Δ = 9
     x' = 8/2 = 4
     x'' = 2/2 = 1
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p) x - 3 = 2√x
    (x-3)² = (2√x)²
     x² - 6x + 9 = 4x
    x² -6x -4x + 9 = 0
    x² - 10x + 9 = 0
    Δ = 100 - 4.1.9
    Δ = 100 - 36
   Δ = 64
   x' = 18/2 = 9
   x'' = 2/2 = 1