√7-5/2 -6-2 √7 /4 +6/2+ √7 -5/ √7-2 Thực hiện phép tính 10/08/2021 Bởi Kennedy √7-5/2 -6-2 √7 /4 +6/2+ √7 -5/ √7-2 Thực hiện phép tính
Đáp án: $\begin{array}{l}\dfrac{{\sqrt 7 – 5}}{2} – \dfrac{{6 – 2\sqrt 7 }}{4} + \dfrac{6}{2} + \dfrac{{\sqrt 7 – 5}}{{\sqrt 7 }} – 2\\ = \dfrac{{\sqrt 7 }}{2} – \dfrac{5}{2} – \dfrac{6}{4} + \dfrac{{\sqrt 7 }}{2} + 3 + 1 – \dfrac{{5\sqrt 7 }}{7} – 2\\ = \left( {\dfrac{1}{2} + \dfrac{1}{2} – \dfrac{5}{7}} \right).\sqrt 7 + 2 – 4\\ = \dfrac{{2\sqrt 7 }}{7} – 2\end{array}$ Bình luận
Đáp án:
$\begin{array}{l}
\dfrac{{\sqrt 7 – 5}}{2} – \dfrac{{6 – 2\sqrt 7 }}{4} + \dfrac{6}{2} + \dfrac{{\sqrt 7 – 5}}{{\sqrt 7 }} – 2\\
= \dfrac{{\sqrt 7 }}{2} – \dfrac{5}{2} – \dfrac{6}{4} + \dfrac{{\sqrt 7 }}{2} + 3 + 1 – \dfrac{{5\sqrt 7 }}{7} – 2\\
= \left( {\dfrac{1}{2} + \dfrac{1}{2} – \dfrac{5}{7}} \right).\sqrt 7 + 2 – 4\\
= \dfrac{{2\sqrt 7 }}{7} – 2
\end{array}$