9. x+5/x-5 - x-5/x+5 = 20/x^2-25
Giải thích
x+5x−5−x−5x+5=20x2−25 (ĐKXĐ: x≠±5)
⇔x+52−x−52x−5x+5=20x−5x+5⇔x2+10x+25−x2+10x−25x−5x+5=20x−5x+5⇔20xx−5x+5=20x−5x+5⇒20x=20⇔x=1 TMS=1
x+5x−5−x−5x+5=20x2−25 (ĐKXĐ: x≠±5)
⇔x+52−x−52x−5x+5=20x−5x+5⇔x2+10x+25−x2+10x−25x−5x+5=20x−5x+5⇔20xx−5x+5=20x−5x+5⇒20x=20⇔x=1 TMS=1