Đinh Hoàng Nghiệp
Giới thiệu về bản thân
V=(x+21+x−21).xx+2
\(= \frac{\sqrt{�} - 2 + \sqrt{�} + 2}{� - 4} . \frac{\sqrt{�} + 2}{\sqrt{�}}\)
\(= \frac{2 \sqrt{�}}{� - 4} . \frac{\sqrt{�} + 2}{\sqrt{�}}\)
\(= \frac{2}{\sqrt{�} - 2}\).
Bạn chưa trả lời câu hP=x2−x1:xx+x+xx+1
\(= \frac{1}{\sqrt{�} \left(\right. � \sqrt{�} - 1 \left.\right)} : \frac{\sqrt{�} + 1}{\sqrt{�} \left(\right. � + \sqrt{�} + 1 \left.\right)}\)
\(= \frac{1}{\sqrt{�} \left(\right. � \sqrt{�} - 1 \left.\right)} . \frac{\sqrt{�} \left(\right. � + \sqrt{�} + 1 \left.\right)}{\sqrt{�} + 1}\)
\(= \frac{1}{� - 1}\).
B=(x+3x−x−3x+1+x−96x+x): (x+3x−3−1)
\(= \left(\right. \frac{�}{\sqrt{�} + 3} - \frac{� + 1}{\sqrt{�} - 3} + \frac{6 � + \sqrt{�}}{� - 9} \left.\right) : \left(\right. \frac{\sqrt{�} - 3}{\sqrt{�} + 3} - 1 \left.\right)\)
\(= \frac{� \left(\right. \sqrt{�} - 3 \left.\right) - \left(\right. � + 1 \left.\right) \left(\right. \sqrt{�} + 3 \left.\right) + 6 � + \sqrt{�}}{� - 9} : \frac{\sqrt{�} - 3 - \sqrt{�} - 3}{\sqrt{�} + 3}\)
\(= \frac{- 3}{� - 9} : \frac{- 6}{\sqrt{�} + 3}\)
\(= \frac{- 3}{� - 9} . \frac{\sqrt{�} + 3}{- 6}\)
\(= \frac{1}{2 \left(\right. \sqrt{�} - 3 \left.\right)} .\)
B=(x+3x−x−3x+1+x−96x+x): (x+3x−3−1)
\(= \left(\right. \frac{�}{\sqrt{�} + 3} - \frac{� + 1}{\sqrt{�} - 3} + \frac{6 � + \sqrt{�}}{� - 9} \left.\right) : \left(\right. \frac{\sqrt{�} - 3}{\sqrt{�} + 3} - 1 \left.\right)\)
\(= \frac{� \left(\right. \sqrt{�} - 3 \left.\right) - \left(\right. � + 1 \left.\right) \left(\right. \sqrt{�} + 3 \left.\right) + 6 � + \sqrt{�}}{� - 9} : \frac{\sqrt{�} - 3 - \sqrt{�} - 3}{\sqrt{�} + 3}\)
\(= \frac{- 3}{� - 9} : \frac{- 6}{\sqrt{�} + 3}\)
\(= \frac{- 3}{� - 9} . \frac{\sqrt{�} + 3}{- 6}\)
\(= \frac{1}{2 \left(\right. \sqrt{�} - 3 \left.\right)} .\)
P=(x+1x+x−1x)(x−x1)
\(= \frac{\sqrt{�} \left(\right. \sqrt{�} - 1 \left.\right) + \sqrt{�} \left(\right. \sqrt{�} + 1 \left.\right)}{� - 1} . \left(\right. \frac{� - 1}{\sqrt{�}} \left.\right)\)
\(= \frac{2 �}{� - 1} . \frac{� - 1}{\sqrt{�}} = 2 \sqrt{�}\).
P=(x+1x+x−1x)(x−x1)
\(= \frac{\sqrt{�} \left(\right. \sqrt{�} - 1 \left.\right) + \sqrt{�} \left(\right. \sqrt{�} + 1 \left.\right)}{� - 1} . \left(\right. \frac{� - 1}{\sqrt{�}} \left.\right)\)
\(= \frac{2 �}{� - 1} . \frac{� - 1}{\sqrt{�}} = 2 \sqrt{�}\).
P=(x+1x+x−1x)(x−x1)
\(= \frac{\sqrt{�} \left(\right. \sqrt{�} - 1 \left.\right) + \sqrt{�} \left(\right. \sqrt{�} + 1 \left.\right)}{� - 1} . \left(\right. \frac{� - 1}{\sqrt{�}} \left.\right)\)
\(= \frac{2 �}{� - 1} . \frac{� - 1}{\sqrt{�}} = 2 \sqrt{�}\).
P=x+2xx+2−x1+x+21
\(= \frac{� + 2 - \left(\right. \sqrt{�} + 2 \left.\right) + \sqrt{�}}{\sqrt{�} \left(\right. \sqrt{�} + 2 \left.\right)}\)
\(= \frac{�}{\sqrt{�} \left(\right. \sqrt{�} + 2 \left.\right)} = \frac{\sqrt{�}}{\sqrt{�} + 2}\)
A=1−a22a2+4−1−a1−1+a1
\(= \frac{2 �^{2} + 4}{1 - �^{2}} - \frac{1 + \sqrt{�} + 1 - \sqrt{�}}{1 - �}\)
\(= \frac{2 �^{2} + 4}{1 - �^{2}} - \frac{2}{1 - �}\)
\(= \frac{2 �^{2} + 4 - 2 \left(\right. 1 + � \left.\right)}{1 - �^{2}}\)
\(= \frac{2 �^{2} - 2 � + 2}{1 - �^{2}}\).
A=1−a22a2+4−1−a1−1+a1
\(= \frac{2 �^{2} + 4}{1 - �^{2}} - \frac{1 + \sqrt{�} + 1 - \sqrt{�}}{1 - �}\)
\(= \frac{2 �^{2} + 4}{1 - �^{2}} - \frac{2}{1 - �}\)
\(= \frac{2 �^{2} + 4 - 2 \left(\right. 1 + � \left.\right)}{1 - �^{2}}\)
\(= \frac{2 �^{2} - 2 � + 2}{1 - �^{2}}\).