Answer:
2.
Step-by-step explanation:
For #2, another way to word this question is: For which of the following trig functions is π/2 a solution? Well, go through them one by one. If you plug π/2 into sinθ, you get 1. This means that when x is π/2, y is 1. Try and visualize that. When y is 1, that means you moved off the x-axis; so y = sinθ is NOT one of those functions that cross the x-axis at θ = π/2. Go through the rest of them. For y = cos(π/2), you get 0. At θ = π/2, this function crosses the x-axis. For y = tanθ, your result is undefined, so that doesn't work. Keep going through them. You should see that y = secθ is undefined, y = cscθ returns 1, and y = cotθ returns 0. If you have a calculator that can handle trig functions, just plug π/2 into every one of them and check off the ones that give you zero. Graphically, if the y-value is 0, the function is touching/crossing the x-axis.
Think about what y = secθ really means. It's actually y = 1/(cosθ), right? So what makes a fraction undefined? A fraction is undefined when the denominator is 0 because in mathematics, you can't divide by zero. Calculators give you an error. So the real question here is, when is cosθ = 0? Again, you can use a calculator here, but a unit circle would be more helpful. cosθ = π/2, like we just saw in the previous problem, and it's zero again 180 degrees later at 3π/2. Now read the answer choices.
All multiples of pi? Well, our answer looked like π/2, so you can skip the first two choices and move to the last two. All multiples of π/2? Imagine there's a constant next to π, say Cπ/2 where C is any number. If we put an even number there, 2 will cut that number in half. Imagine C = 4. Then Cπ/2 = 2π. Our two answers were π/2 and 3π/2, so an even multiple won't work for us; we need the odd multiples only. In our answers, π/2 and 3π/2, C = 1 and C = 3. Those are both odd numbers, and that's how you know you only need the "odd multiples of π/2" for question 3.
Answer:
x=54
Step-by-step explanation:
2x + 2 = 3x - 52
subtract 2x from both sides, now u have:
2 = x - 52
add 52 from both sides, now u have
54 = x
Answer:
10582
Step-by-step explanation:
Answer:
- This is a biased sampling method for obtaining customer opinions because those who take the time to write an online review are likely to do so because they are upset with the service they received.
- The direction of the bias is likely to overestimate the proportion of customers who have a negative opinion on the service.
Step-by-step explanation:
1) There are groups which are not represented in the survey like those who don't use web. And also those who take the time to write an online review are likely to do so because they are upset with the service they received.
2) Those who had negative experience are more likely to write a review than those who had not.
Answer:
Ordinary Least Square (OLS) for the multiple regression model involves selecting parameters of a straight line function that will minimize <u>the sum of the squares of the variance in the given dataset and those forecasted by the straight-line function.</u>
Cheers
