With this method we can write a polynomial as a text to avoid extra symbols such as "1x+-3x+1".

[code]ua = Slider(-1, 1, 0.1, 1, 150, false,true, false,false)[br]ub = Slider(-1, 1, 0.1, 1, 150, false,true, false,false)[br]uc = Slider(-1, 1, 0.1, 1, 150, false,true, false,false)[br][br]I1 = InputBox(ua)[br]I2 = InputBox(ub)[br]I3 = InputBox(uc)[br][br]f1(x) = ua x^2+ ub x + uc[br]f2(x) = ua x^2 + uc[br]f3(x) = ub x + uc[br]f4(x) = uc[br][br]t1 = If(ua !=0 && ub!= 0 , f1, If( ua!=0 && ub==0, f2, If( ua==0&& ub!=0, f3, If( ua==0 && ub==0, f4) ) ))[br][br][/code]