## Question

A focus of an ellipse is at the origin. The directrix is the line *x* = 4 and the eccentricity is 1/2. Then the length of the semi-major axis, is

### Solution

8/3

Let the length of semi-major and semi-minor axes be *a* and *b*respectively

We have,

Distance between focus and directrix = 4.

.

#### SIMILAR QUESTIONS

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