Dandelion coffee In 1919, dandelion root was noted as a source of cheap 'coffee'. It has also been part of edible plant classes dating back at least to the 1970s. Harvesting dandelion roots requires differentiating 'true' dandelions ("Taraxacum" spp.) from other yellow daisy-like flowers such as catsear and hawksbeard. True dandelions have a ground-level rosette of deep-toothed leaves and hollow straw-like stems. Large plants that are 3–4 years old, with taproots approximately 0.5 inch (13 mm) in diameter, are harvested for dandelion coffee. These taproots are similar in appearance to pale carrots. After harvesting, the dandelion roots are dried, chopped, and roasted.
Nth root positive "n"th root, called the principal "n"th root, which is written formula_6. For "n" equal to 2 this is called the principal square root and the "n" is omitted. The "n"th root can also be represented using exponentiation as "x". For even values of "n", positive numbers also have a negative "n"th root, while negative numbers do not have a real "n"th root. For odd values of "n", every negative number "x" has a real negative "n"th root. For example, −2 has a real 5th root, formula_29 but −2 does not have any real 6th roots. Every non-zero number "x",