<prompt> Pata thamani ya chini ya chaguo za kukokotoafx sqrt-x2 4x 21 - sqrt-x2 3x 10.  <response>: Tunaweza kuandika kazi kamafx sqrt7 - x3 x - sqrt5 - x2 x.Hii inaonyesha kuwa chaguo la kukokotoa limefafanuliwa kwa - pekee 2 le x le 5. Pia, 7 - x3 x - 5 - x2 x x 11 0 kwa muda huu, ambayo ina maana kwamba f x ni chanya kila wakati.Kishaanzaalignfx2 7 - x3 x - 2 sqrt7 - x3 x sqrt5 - x2 x 5 - x 2 x -2x2 7x 31 - 2 sqrt7 - x2 x5 - x3 x 2 7 - x2 x - 2 sqrt7 - x2 x sqrt5 - x3 x 5 - x 3 x 2 kushoto sqrt7 - x2 x - sqrt5 - x3 x kulia2 ge 2.endalignKwa hivyo, fx ge sqrt2.Usawa hutokea wakati 7 - x2 x 5 - x3 x, au x frac13. Tunahitimisha kwamba thamani ya chini ni sqrt2. 