# Canonicalize radical not simplifying expression

I have the expression
`7/6528*(103*sqrt(sqrt(17) + 17)*(sqrt(17) - 17) + 252*sqrt(17)*sqrt(-sqrt(17) + 17))/(sqrt(sqrt(17) + 17)*(sqrt(17) - 17))`

, which I know is a rational number based on a theorem proved from a paper. In fact, it is supposed to equal `35/816`

. However, SageMath does not simplify this to a rational number with `full_simplify()`

or with `canonicalize_radical()`

.

How do I force SageMath to simplify this properly?