If two tangents of circle (x-1) × (x-1) + y × y = 1 can be made through points (5a + 1,12a), then the value range of real number a is

If two tangents of circle (x-1) × (x-1) + y × y = 1 can be made through points (5a + 1,12a), then the value range of real number a is

As long as the point (5a + 1,12a) is not on the circle, two tangents can be made=_ Therefore, the value range of a is all real numbers where a is not equal to + 1 / 13 or - 1 / 13

If point P (5a, 12a) is in the unit circle, then the value range of a is?

The distance from point P to the origin is 13A (Pythagorean theorem). The square of 5A plus the square of 12a is equal to 13 | a |. Point P is in the unit circle, and the center of the unit circle is the origin, so 13 | a | < 1, so the value range of a is - 1 / 13