y=a√(1+b²)>0
y²=a²(1+b²)=a²(1+2+2a²)=-2(a²-(3/4)²)+2(3/4)²
y²最大=2(3/4)²
y最大=3/4√2
y=√(ax^2+2ax+1)
ax^2+2ax+1>=0
y1=ax^2+2ax+1>=0
y1的顶点在X轴的上方,开口向上.
a>0,(4a-4a^2)/4a>=0,a1-a
当1>=a>=1/2时,x>a
当0
y=a√(1+b²)>0
y²=a²(1+b²)=a²(1+2+2a²)=-2(a²-(3/4)²)+2(3/4)²
y²最大=2(3/4)²
y最大=3/4√2
y=√(ax^2+2ax+1)
ax^2+2ax+1>=0
y1=ax^2+2ax+1>=0
y1的顶点在X轴的上方,开口向上.
a>0,(4a-4a^2)/4a>=0,a1-a
当1>=a>=1/2时,x>a
当0