In angles very close to 90 degrees, a small error can make a very large difference. If the angle was really 89.8 degrees, the result would be very far from the result with 89.5 degrees.

## 89.5 is not a good approximation if it really was 89.8 degrees.

In angles very close to 90 degrees, a small error can make a very large difference. If the angle was really 89.8 degrees, the result would be very far from the result with 89.5 degrees.