Jika (x – 1/x) = 1/2, hitunglah (4x^2+4/x^2)

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Jika (x – 1/x) = 1/2, hitunglah (4x^2+4/x^2)

Jawaban:

{4x}^{2} + frac{4}{ {x}^{2} } =9 \

Penjelasan dengan langkah-langkah:

(x - frac{1}{x}) = frac{1}{2} \

Kedua ruas dikalikan 2

(x - frac{1}{x}) = frac{1}{2} \ 2(x - frac{1}{x}) = 2(frac{1}{2}) \ (2x - frac{2}{x}) = 1\

Kuadratkan kedua ruas

(2x - frac{2}{x})^{2} = {1}^{2} \ {4x}^{2} - 2(2x)( frac{2}{x}) + frac{4}{ {x}^{2} } = 1 \ {4x}^{2} - 8 + frac{4}{ {x}^{2} } = 1 \ {4x}^{2} + frac{4}{ {x}^{2} } = 1 + 8 \ {4x}^{2} + frac{4}{ {x}^{2} } =9

Semoga membantu.

Note:

(a – b)² = a² – 2ab + b²