{
  "aliases": null,
  "backlinks": null,
  "body": "\n## Definition\n\nLet $f \\colon [0, \\infty) \\to \\C$ be a [[function|0XHDTE5YMZ]] and let $a \\in \\R$.\nThe function $f$ is *of exponential order $a$* if there are constants $M \u003e 0$ and $T \\ge 0$ such that\n$$\\abs{f(t)} \\le M e^{at} \\quad \\text{for all } t \\ge T,$$\nwhere $e^{at}$ is the [[exponential function|0RMVS7RXZX]].\nThe function $f$ is *of exponential order* if it is of exponential order $a$ for some real $a$.\n\n## Remarks\n\nExample: $f(t) = t^n$ with $n \\in \\N$ is of exponential order $1$, since $e^t \\ge t^n / n!$ for $t \\ge 0$ by the power series of $e^t$; so $\\abs{f(t)} \\le n!\\, e^t$ with $T = 0$.\nIn fact $t^n$ is of exponential order $a$ for every $a \u003e 0$.\nNon-example: $f(t) = e^{t^2}$ is not of exponential order, since $e^{t^2}/e^{at} = e^{t(t - a)} \\to \\infty$ for every real $a$.\nA bounded function, such as $\\sin t$, is of exponential order $0$.\nSome books require the bound for all $t \\ge 0$ ($T = 0$); for functions that are bounded on bounded intervals the two versions agree, after enlarging $M$.\n",
  "commit": "ff8a40749dc16545e3d2fc637f6b0196e81d0bfa",
  "front": {
    "defines": "TKZAV3KR86",
    "kind": "definition",
    "msc": [
      "44A10"
    ],
    "name": "Function of exponential order",
    "sources": [
      {
        "url": "https://en.wikipedia.org/wiki/Laplace_transform"
      }
    ],
    "tag": "Y5CC9MSGYM",
    "uses": [
      "0XHDTE5YMZ",
      "0RMVS7RXZX"
    ]
  },
  "kind": "definition",
  "link": "https://tamnd.github.io/math2/node/Y5CC9MSGYM/",
  "links": [
    {
      "field": "defines",
      "target": "TKZAV3KR86"
    },
    {
      "field": "uses",
      "target": "0XHDTE5YMZ"
    },
    {
      "field": "uses",
      "target": "0RMVS7RXZX"
    }
  ],
  "markdown": "https://tamnd.github.io/math2/node/Y5CC9MSGYM.md",
  "msc": [
    "44A10"
  ],
  "name": "Function of exponential order",
  "prov": null,
  "role": "",
  "source": "https://github.com/tamnd/math2/blob/main/nodes/Y5C/Y5CC9MSGYM.md",
  "status": null,
  "tag": "Y5CC9MSGYM",
  "uri": "m2://Y5CC9MSGYM",
  "url": "https://tamnd.github.io/math2/wiki/function-of-exponential-order-definition/",
  "writing": {
    "tag": "Y5CC9MSGYM",
    "kind": "definition",
    "level": "W0",
    "next": [
      {
        "what": "an inventory row",
        "note": "the row of the inventory that the node accounts for",
        "have": 0,
        "want": 1
      },
      {
        "what": "a source with a locator",
        "have": 0,
        "want": 1
      }
    ]
  }
}
