[tex]a)\\\text{dla } x = -\frac12\\4x^2-3x-6=4*(-\frac12)^2-3*(-\frac12)-6=4*\frac14+\frac32-6=1+1.5-6=2.5-6=-3.5\\\text{dla } x = \frac14\\4x^2-3x-6=4*(\frac14)^2-3*\frac14-6=4*\frac1{16}-\frac34-6=\frac{4}{16}-\frac34-6=\frac{1}4-\frac34-6=-\frac12-6=-6.5[/tex]
b)
[tex]\text{dla } x = -\frac12\\-8*(-\frac12)^2+4-1=-8*\frac14+3=-2+3=1\\\text{dla }x=\frac14\\\\-8*(\frac14)^2+4-1=-8*\frac1{16}+3=-\frac12+3=2.5[/tex]
c)
[tex]\text{dla } x = -\frac12\\-2*(-\frac12)^2-6+\frac12=-2*\frac14-5\frac12=-\frac12-5\frac12=-6\\\text{dla } x = \frac14\\-2*(\frac14)^2-6+\frac12=-2*\frac1{16}-6+\frac12=-\frac18-6+\frac12=-6\frac18+\frac{4}8=-5\frac{9}8+\frac48=-5\frac58[/tex]
