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diff --git a/pl/math/tools/tan.sollya b/pl/math/tools/tan.sollya
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+// polynomial for approximating double precision tan(x)
+//
+// Copyright (c) 2023, Arm Limited.
+// SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
+
+deg = 8;
+
+// interval bounds
+a = 0x1.0p-126;
+b = pi / 8;
+
+display = hexadecimal;
+
+f = (tan(sqrt(x))-sqrt(x))/x^(3/2);
+poly = fpminimax(f, deg, [|double ...|], [a*a;b*b]);
+
+//print("rel error:", accurateinfnorm(1-poly(x)/f(x), [a;b], 30));
+print("in [",a,b,"]");
+print("coeffs:");
+for i from 0 to deg do coeff(poly,i);