<prompt> Acha fx iwe kazi ambayo f0 1 nafxy f left fracx2 y22 kulia x - y2kwa nambari zote halisi x na y. Tafuta fx.  <response>: Kuweka y 0, tunapataf0 f left fracx22 kulia x2.Kwa hivyo, fu 1 - 2u kwa u yote ge 0 .Kuweka y 1, tunapatafx f left fracx2 12 kulia x - 12 1 - 2 cdot fracx2 1 2 x - 12 1 - 2x. 