Make cos c the subject of c^2=a^2+B^2-2ab Cos C
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Find the multiplicative inverse of 8-12i

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?

Write the summation to estimate the area under the curve y = 1 + x2 from x = -1 to x = 2 using 3 rectangles and right endpoints