Question

como calcula 3x²+4x-1 , para x= 0,5

Answer 1

3.0,5^2+4.0,5-1
3.0,25+2-1
0,75+1
1,75

Answer 2

$3x^2+4x-1 \\ \\ x=0,5= \frac{1}{2} \\ \\ 3 ( \frac{1}{2}) ^{2} +4. \frac{1}{2} -1= \\ \\ = 3\frac{1^2}{2^2} +2-1= \\ \\ =3 \frac{1}{4} +2-1= \\ \\ = \frac{3}{4} +2-1= \\ \\ = \frac{3+4.2-4.1}{4} = \frac{3+8-4}{4} = \frac{7}{4} =1,75$