Learning Guide Learning Guide

156 • Chapter 5: Evaluation and Simplification> expr := (x - 1/x) / (x-2);expr :=x − 1 xx − 2> normal( expr );x 2 − 1x (x − 2)Use the second argument expanded if you want normal to expand thenumerator and the denominator.> normal( expr, expanded );x 2 − 1x 2 − 2 xThe normal command acts recursively over functions, sets, and lists.> normal( [ expr, exp(x+1/x) ] );x 2 − 1[x (x − 2) , e( x2 +1x ) ]> big_expr := sin( (x*(x+1)-x)/(x+2) )^2> + cos( (x^2)/(-x-2) )^2;big_expr := sin((x + 1) x − xx + 2x 2) 2 + cos(−x − 2 )2> normal( big_expr );x2x2sin(x + 2 )2 + cos(x + 2 )2Note from the previous example that normal does not simplifytrigonometric expressions, only rational polynomial functions.