Because y(x)=(1/k) cosh [k(x+a)]+b' The ad is in great condition.
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The Texas Instruments TI-89 calculator is a vintage model made in the United States. It is a part of the consumer electronics category and is a sought-after item for collectors of vintage calculators and electronics.
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Texas Insruments TI-89 Calculator Preowned Vg Condition.#750
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The ad is in great condition!
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