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2.12.11  Zeros of an expression : zeros

zeros takes as argument an expression depending on x.
zeros returns a list of values of x where the expression vanishes. The list may be incomplete in exact mode if the expression is not polynomial or if intermediate factorizations have irreducible factors of order strictly greater than 2.
In real mode, (complex box unchecked in the Cas configuration or complex_mode:=0), only reals zeros are returned. In (complex_mode:=1) reals and complex zeros are returned. See also cZeros to get complex zeros in real mode.
Input in real mode :

zeros(x^2+4)

Output :

[]

Input in complex mode :

zeros(x^2+4)

Output :

[-2*i,2*i]

Input in real mode :

zeros(ln(x)^2-2)

Output :

[exp(sqrt(2)),exp(-(sqrt(2)))]

Input in real mode :

zeros(ln(y)^2-2,y)

Output :

[exp(sqrt(2)),exp(-(sqrt(2)))]

Input in real mode :

zeros(x*(exp(x))^2-2*x-2*(exp(x))^2+4)

Output :

[[log(sqrt(2)),2]

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