### 10.2.11 Transforming arctan into arcsin

The atan2asin command transforms any arc tangents in an expression to arc sines by using the identity

arctan(x)=arcsin

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x

√

1+x2

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- atan2asin takes expr, an expression containing inverse trigonometric functions.
- atan2asin(expr) returns expr with all instances of atan replaced according to the above formula.

#### Example

atan2asin(atan(x))

arcsin

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x

√

1+x2

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