# Functions

Pro Problems > Math > Algebra > Functions# Featured Pro Problems

Two time-based arithmetic series combined at different rates

An arithmetic series problem involving overdue library books

Solve the problem involving an isosceles triangle embedded in a right triangle

Fractional sine, cosine, and tangent functions, in terms of the variable a

Simplify the trigonometric expression shown in the trig problem

Simplify this fourth degree trigonometric expression involving functions of 15 degrees

Find the cosine of the given angle, based on information provided on three component angles

Calculate the cos(2A), given information about angle A and a sum of angles equation

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