# exp of quaternion

I try

```
Q.<i,j,k> = QuaternionAlgebra(SR, -1, -1)
exp(x+i*x+j*x+k*x)
```

I get

TypeError: cannot coerce arguments: no canonical coercion from Quaternion Algebra (-1, -1) with base ring Symbolic Ring to Symbolic Ring

what means "-1,-1"? How to expand as demoivre() this?