Explanation for Question 14 From the Math (No Calc) Section on the 2019 October Sat
Now in question number 14, we're asked which of the following is equivalent to 2 our, to the two fifth, two fifths time, 3 the square root of our, where our is greater than zero. 4 Um, just for clarity, the reason they say that R is greater than zero 5 is because you're taking the square root of R. 6 So that means our is not allowed to be negative because you can't take 7 the square root of a negative number. In reality, 8 you don't need to know of why they put that there or what that 9 means. It doesn't really change the math of the problem. 10 But if that was what confused, you just know that it's there because you 11 can't take the square root of a negative number. 12 So now let's get into the math, right? We noticed that all of our 13 answer choices have the, um, 14 the exponent as a fraction, right? 15 And one of our, our turns has the exponent as a fraction, 16 but the square root does not. So step one is taking that square root 17 and changing it so that it has an exponent of a fraction rather than 18 a radical. And one thing we need to know about a square root is 19 that there's an invisible two. If they have no number written right here, 20 sometimes you'll see a number there like a three, for instance. 21 Um, but in this case, there's no number. 22 So we know that there's an invisible too, right? 23 And when we have just our it's also like there's an invisible one on 24 the R. So what we can do here is we can rewrite this where 25 we haven't are raised to a fraction...