### 10.2.10 Transforming arcsin into arctan

The asin2atan command transforms arc sines in an expression to arc tangents by using the identity

arcsin(x)=arctan

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x

√

1−x2

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.

- asin2atan takes expr, an expression containing inverse trigonometric functions.
- asin2atan(expr) returns expr with all instances of asin replaced according to the above formula.

#### Example

asin2atan(asin(x))

arctan

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x

√

1−x2

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⎠