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The trigonometric ratios sine and secant are reciprocals of each other

There are 45 questions on your math exam. you answered 810 of them correctly. how many questions did you answer correctly?

(c) the diagram shows the first three shapes of a matchsticks arrangement.first shape = 3second shape = 5third shape = 7given m represents the number of matchstick used to arrange the n'th shape.(i) write a formula to represent the relation between m and n. express m as the subjectof the formula.(ii) 19 matchsticks are used to make the p'th shape. find the value of p.