Given that the diameter of the circle is 5cm, the chord ab ‖ CD, ab = 3cm, CD = 4cm, find the large distance between AB and CD

Given that the diameter of the circle is 5cm, the chord ab ‖ CD, ab = 3cm, CD = 4cm, find the large distance between AB and CD

Connect AO and co respectively, make the vertical line of AB and CD through O, and the vertical feet are e and f respectively,
Obviously, EF is the maximum distance between AB and CD,
According to the vertical diameter theorem, AE = 3 / 2, CF = 2,
In the right angle △ AEO, from the Pythagorean theorem, EO = 2,
Similarly, fo = 3 / 2,
∴EF=7／2,
The maximum distance between AB and CD is 3.5 cm

What kind of graph is the set of points whose distance is equal to 1.5cm
If AB = 2cm, the distance between points a and B is equal to 1.5cm, what kind of graph is the set of points

The set of points is a circle
Add two points AB, well, draw a regular diamond with a side length of 1.5 and a long diagonal of 2, and then turn around with this long diagonal as the axis It is a stereogram
Do not know the specific name, can only be described in this way, ha ha

Given that the length of line AB is 5cm, is there a point C so that the sum of the distances from a and B is equal to 4? Why?
Another is: when the sum of the distances from point C to a and B is equal to 4cm, where should point C be? Why?

There is no point C so that the sum of the distances to a and B is equal to 4
If C is on the line AB, then the sum of its distances from a and B is equal to 5
If C is outside the line AB, the distance from C to a is greater than that on the line AB, so is the distance from C to B
So there is no such point C