series (sin (x),x,pi /2)

solve(1 - x**2/2 + x**4/24 + O(x**6), x)

diff(1 - x**2/2 + x**4/24 + O(x**6), x)

series(1 - x**2/2 + x**4/24 + O(x**6), x, 0, 10)

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