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222-9+11+12:2*14+14 = ? ( )

Toán Lớp 9: 3 √4x+4 – √9x+9 – 8 √x+1/16 = 5

Toán Lớp 9: 3 √4x+4 – √9x+9 – 8 √x+1/16 = 5

Comments ( 2 )

  1. Giải đáp+Lời giải và giải thích chi tiết:
    3\sqrt{4x+4}-\sqrt{9x+9}-8\sqrt{\frac{x+1}{16}}=5(x>=-1)
    <=>3\sqrt{4(x+1)}-\sqrt{9(x+1)}-8\sqrt{\frac{1}{16}(x+1)}=5
    <=>3.2\sqrt{x+1}-3\sqrt{x+1}-8.\frac{1}{4}\sqrt{x+1}=5
    <=>6\sqrt{x+1}-3\sqrt{x+1}-2\sqrt{x+1}=5
    <=>(6-3-2)\sqrt{x+1}=5
    <=>\sqrt{x+1}=5
    <=>(\sqrt{x+1})^2=5^2
    <=>x+1=25
    <=>x=24(tm)
    Vậy S={24}
     

  2. ĐK: x ≥ -1
    3$\sqrt[]{4x+4}$ -$\sqrt[]{9x+9}$ – $\frac{8\sqrt[]{x+1}}{16}$ = 5
    ↔ 6$\sqrt[]{x+1}$ -3$\sqrt[]{x+1}$ – $\frac{\sqrt[]{x+1}}{2}$ = 5
    ↔ $\sqrt[]{x+1}$ (6 – 3 + $\frac{1}{2}$) = 5
    ↔ $\sqrt[]{x+1}$ . $\frac{7}{2}$ = 5
    ↔ $\sqrt[]{x+1}$ = $\frac{10}{7}$
    ↔ x + 1 = $\frac{100}{49}$
    ↔ x = $\frac{51}{49}$( tm )

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222-9+11+12:2*14+14 = ? ( )