curl --request POST \
  --url https://api.iotools.cloud/v1/tool/binomial-theorem-expansion-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "termA": "2x",
  "termB": "3",
  "exponent": "4"
}
'

{
  "tool": "binomial-theorem-expansion-calculator",
  "tool_version": "1.0.2",
  "outputs": {
    "expression": "(2x + 3)^4",
    "expansion": "(2x + 3)^4 = 16x^4 + 96x^3 + 216x^2 + 216x + 81",
    "terms": [
      {
        "k": "0",
        "c-n-k": "1",
        "coefficient": "16",
        "term": "16x^4"
      },
      {
        "k": "1",
        "c-n-k": "4",
        "coefficient": "96",
        "term": "96x^3"
      },
      {
        "k": "2",
        "c-n-k": "6",
        "coefficient": "216",
        "term": "216x^2"
      },
      {
        "k": "3",
        "c-n-k": "4",
        "coefficient": "216",
        "term": "216x"
      },
      {
        "k": "4",
        "c-n-k": "1",
        "coefficient": "81",
        "term": "81"
      }
    ],
    "termCount": "5",
    "sumBinomialCoefficients": "16",
    "sumCoefficients": "625"
  },
  "credits_used": 5,
  "credits_remaining": null
}