What is the domain of f(x) = cos(x)? the set of real numbers Negative 2 pi less-than-or-equal-to x less-than-or-equal-to 2 pi the set of real numbers Negative 1 less-than-or-equal-to x less-than-or-equal-to 1 the set of real numbers 0 less-than-or-equal-to x less-than-or-equal-to 2 pi the set of all real numbers

In factoring by grouping, what would you have for step 3 for the following? step 1: x^3 +5x^2 +4x+20 step 2: x^2 (x+5)+4(x+5) step 3: ?

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Lin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. she knows that the total cost to download 3 videos was $12. her work to find the equation is shown below. joylin’s work step 1 k= 3/12= 0.25 step 2 y= 0.25x where did joylin make her first error?