Numerari from KnowledgeDoor---The scientific calculator with graphing, unit keypads,
complex numbers, constants, advanced functions, user-defined keys, quick copy, and more! Learn more (Link leaves KnowledgeDoor website)

What do we mean by "exact"?

When we say that a value is exact, we mean that it is defined by law, standards committees, or mathematics and it is not a measured value. For example, an inch is defined to be exactly 2.54 centimeters.

Heaven's Boulevard astronomical sky image for any location, date, and time. Personalize with a picture and message. Great gift for birthdays, anniversaries, or any special event. Learn more
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