Question

数学的好的进来教教我呐写出对称轴 y=x2-2x+3 y=2x-x+1 y=-x2+x+2 y=-2x+3x+5 X后面

Answer 1

y=x²-2x+3

=x²-2x+1+2

=(x-1)²+2

所以对称轴x=1

y=2x²-x+1

=2(x²-x/2+1/16-1/16)+1

=2(x-1/4)²+7/8

所以对称轴x=1/4

y=-x³+x+2

=-(x²-x+1/4-1/4)+2

=-(x-1/2)²+9/4

所以对称轴x=1/2

y=-2x²+3x+5

=-2(x²-3x/2+9/16-9/16)+5

=-2(x-3/4)²+49/5

所以对称轴x=3/4