ax+by = c. - 7 a The sum, S,, of the first n terms of an arithmetic progression is given by S first term and the common difference. b The first term of a geometric progression is 24 and the fourth term is 12 Fin i the common ratio ii the sum to infinity. 8 The equation of a curve is y = 3 + 12x - 2x². a Express 3+ 12x - 2x² in the form a -2(x + b)2, where a and b are constants Find the coordinates of the stationary point on the curve. Find the set of values of x for which y < -5. b c

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Find the transition points. y = 15x³ + 360x² (Use symbolic notation and fractions where needed. Give your answer in the form of a comma separated list) x = -8 Incorrect Find the interval(s) of increase. (Use symbolic notation and fractions where needed. Give your answer as interval(s) in the form (*, *). Use the symbol ∞ for infinity, U for combining intervals, and an appropriate type of parenthesis "(", ")", "[", "]" depending on whether the interval is open or closed. If the interval does not exist, enter Ø). x E (-∞0,-16) U (0,00) Find the interval(s) of decrease. (Use symbolic notation and fractions where needed. Give your answer as interval(s) in the form (*, *). Use the symbol ∞ for infinity, U for combining intervals, and an appropriate type of parenthesis "(", ")", "[", "]" depending on whether the interval is open or closed. If the interval does not exist, enter Ø). XE (-16,0) Find the interval(s) on which the function is concave up. (Use symbolic notation and fractions where…