(3x-1)/(x+2)=[3(x+2)-7]/(x+2)=3-7/(x+2) 于是函数变形成为y=3-7/(x+2)--->y-3=-7/(x+2) 对应的函数Y=-7/X的中心是原点，对称轴是Y=+'-X 于是原函数图像的中心是点(-2,3),对称轴方程是y-3=+'-(x+2),就是x-y+5=0,x+y-1=0.
问：函数若Y=f(2x+1)是偶函数,则函数y=f(2x)+1的图象的对称轴方程为( ) A.x=-1 B.x=1 C.x=-1/2 D.x=1/2
答：选D 设t=2x没，∵ y=f(1+t)是偶函数, ∴ f(1-t)=f(1+t), f[1-(1-t)]=f[1+(1-t)], 即f(t)=f(2-t), ...详情>>
答：One Sunday, Mark decided to go sailing in his boat with his friend Dan, but Dan ...详情>>
