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I have a very long formula. There are variables R_1, and R. Every time when I change the value of R. like R=1, and R_1 also change to 1_1. Is there any way to make R and R_1 be two completely individual variables? Thanks!
Hi, I am a new user of mathematica. I was trying some functions to get familiar with mathematica. After that, when I input I (imaginary unit), the output only display a red rectangle. And I found, all complex numbers displayed a red rectangle. I can...