Question: modifying or sorting an expression of a fraction

Hello people in mapleprimes,

I want to modify the following expression a to b. For it, I used c code.
But, as seen in d, just using c returns a. Originally, I intended phi being between 0 and 1, so
that 1-phi >0. Isn't any better way to modify a to b? and it is better to have maple sort expression remembering 1-phi to be positive, and to have maple give any priority to it in modifying a to b.

(-2*theta+1)*phi/(phi-1) + theta

I will be very glad if you borrow me your idea.

Thank you in advance.

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