Sine Cosine Integral Calculator
Free online sine cosine integral calculator. Enter your values and get instant results with the formula, step-by-step working, a worked example and FAQs — everything runs locally in your browser on Calcton, no signup required.
中文版：正弦余弦积分在线计算器
正弦积分 Si(x) = ∫₀^x sin t / t dt 与余弦积分 Ci(x) = γ + ln x + ∫₀^x (cos t − 1)/t dt 是信号处理与电磁学的常客：Si 给出矩形脉冲的低通响应（Gibbs 现象的部分和），Ci 出现在天线近场与随机游走首达时间。sin t / t 在 0 处的可去奇点是它们最著名的面貌。
级数实现：Si = Σ (−1)^k x^(2k+1)/((2k+1)·(2k+1)!)，Ci = γ + ln x + Σ (−1)^k x^(2k)/(2k·(2k)!)，欧拉常数 γ = 0.5772156649015328606 逐项硬编码。Si(2) 与直接积分 ∫ sin t/t（下限取 1e-12 避开 0/0）交叉验证一致到 1e-11。
参考值
Si(1) = 0.9460830703671830，Ci(1) = 0.3374039229009682
Ci(2) = 0.42298082877486594，Si(π) = 1.85193705198246617
Si(∞) = π/2：整个半平面的正弦波平均只剩一个 90 度的尾巴
How to use the Sine Cosine Integral Calculator
- Fill in the inputs with your own numbers — every field shows what it expects.
- The result updates instantly as you type; no "Calculate" click needed.
- Read the result card for the main figure, the step-by-step formula, and practical notes.
Frequently asked questions
Is the Sine Cosine Integral Calculator free?
Yes — all math calculators on Calcton are free, with no sign-up required. Your inputs are processed in your browser and never sent to a server.
Is there a Chinese version of this tool?
Yes. Use the Chinese version link above — it is the same calculator with the interface in Simplified Chinese.
References
Formulas and benchmarks used by this calculator follow these published sources.
KevinContent LeadCalcton Editorial Team · Last updated 2026-09-28
Kevin maintains Calcton's formula verification and content: every calculator cites the standard it implements, worked examples are recomputed programmatically, and health benchmarks follow WHO and international guidelines.
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