@42:00 if you solve by substituting negative x and positive x (2 possible scenarios with absolute values), one of your simplified answers (as the instructor realized when scribbling), is x squared is less than or equal to negative 4 (and the other solution is x squared is greater than or equal to 2). The GRE doesn't recognize the former equation though (the x squared is less than or equal to negative 4 one) b.c x squared can never be negative on the GRE. As a result, shouldnt the answer be D?
@@kumarneupane6699I am probably replying very late but the only answer to that is if we take any +ve value of X, then the first equation fails so we have no other option than taking X negative.
The right answer to the original question is (D). However, at that point in the lesson, Cat altered the problem so that it said "y is a positive integer," not just an integer. In that case, the givens would tell you something about y, and the answer would change to (B).
@@manhattanprepgre7390 Thank you for your reply. It will be awesome if instructor can highlight the answer to 'original' question. I too was confused as to what the correct answer is for the original question.
In QC questions are the statements interlinked or independent cuz in the 2nd QC question, there is a probability of a and c being positive. Which makes the answer D
@@manhattanprepgre7390 even if u plug in numers it will still show D as answer, we dont even know if AB, so D is correct answer... try plugging in numbers still gives different answers so D
@45:00 the answers is wrong it shouldn't be option B it should be D The math was a little wrong as we know x is -ve -X|X| >= 4 putting the -ve value -X(-)|-X| >= 4 X * X >= 4 (because |-X| = X) X^2 >= 4 X >= 2 and X
Ma'am, there is 2 type of books of manhattan 5lb, one in green color cover and second in black cover. which one is better. And what to know before taking a book. please tell me.
Hi there! You can see the most current edition of the book here: www.manhattanprep.com/gre/store/gre-strategy-guides/5-pound-book-gre-practice-problems
For the problem around 42 minutes - once you establish that x is negative, why do you need to go on to solve the inequality? Won't you know that x is less than 2 by knowing that x is negative??
@45:19 how we can take the square root of a negative integer, it is not possible. Even if we take, we will get iota (I) with the integer 2 which is not in the syllabus of GRE. Please clarify if I am wrong.
Hi! We checked with Cat on this and here's what she had to say: "Hi! So I think the way I notated/explained this wasn't as clear as it could be. You're correct that we can't take the square root of a negative integer. Here, though, because I'm working with absolute value, I'm using the squared notation just to think about what x could be in the upfront information (and in that case, x can equal a negative, since we aren't squaring x, but rather multiplying x by the absolute value of x, and then by negative 1.) Apologies that the way I explain that in the video led to confusion!"
for the first problem, I chose a = -1 and b = -1 and the result gave me a positive number. I don't get why it could no be D or A on the second problem, I solved inequalities as follows: 3x - 21 ≥ 9 +21 +21 3x≥30 /3 /3 x ≥ 10 0.25y - 3 ≤ 1 +3 +3 0.25y ≤ 4 /0.25 /0.25 y ≤ 1 Why is this is this 0.25y ≤ 4 multiplied by 4?
This is nice answers how to know which is equal to which
Hi Cat! @20:00 , I feel like the answer is D, what if a is positive and c is positive?
@42:00 if you solve by substituting negative x and positive x (2 possible scenarios with absolute values), one of your simplified answers (as the instructor realized when scribbling), is x squared is less than or equal to negative 4 (and the other solution is x squared is greater than or equal to 2). The GRE doesn't recognize the former equation though (the x squared is less than or equal to negative 4 one) b.c x squared can never be negative on the GRE. As a result, shouldnt the answer be D?
Same thought i had!
@Manhattan Prep GRE, I feel the same, Plz reply !!
@@kumarneupane6699I am probably replying very late but the only answer to that is if we take any +ve value of X, then the first equation fails so we have no other option than taking X negative.
I got reply today and I confused about what my original query was 😂. It’s been 2 years and I’m already doing PhD in US (2nd year) lol 😂😂
@@kumarneupane6699 sorry man, came across this video today! I have my GRE on the 11th of this month. So was revising a few important concepts!
But cant we have ac as -a and -c which will give a positive.
yes, even i was like why she is not considering both negatives.
the answer to 2nd question is D not B please correct it
Chrissy knows it all
i think that b must be greater than zero is correct
In 40:35, are you sure that the answer is B and not D? She laterally said we know nothing about y and then chose B..... I am confused.....
The right answer to the original question is (D). However, at that point in the lesson, Cat altered the problem so that it said "y is a positive integer," not just an integer. In that case, the givens would tell you something about y, and the answer would change to (B).
@@manhattanprepgre7390 Thank you for your reply. It will be awesome if instructor can highlight the answer to 'original' question. I too was confused as to what the correct answer is for the original question.
In QC questions are the statements interlinked or independent cuz in the 2nd QC question, there is a probability of a and c being positive. Which makes the answer D
The statements are interlinked! So whatever a variable represents in one statement, it has to represent the same thing in the other statement.
@@manhattanprepgre7390 even if u plug in numers it will still show D as answer, we dont even know if AB, so D is correct answer... try plugging in numbers still gives different answers so D
Feeling sleepy tonight. I'll come back to watch
@45:00 the answers is wrong it shouldn't be option B it should be D
The math was a little wrong as we know x is -ve
-X|X| >= 4
putting the -ve value
-X(-)|-X| >= 4
X * X >= 4 (because |-X| = X)
X^2 >= 4
X >= 2 and X
Correction : option B is the correct answer because we know x should be negative so X
Thankyou for the video
I got them all right!!
Can you please recommend any sources for practice of these particular question types?
@@angryprogrammer7788 manhattan series for maths. They are perfect for developing a good understanding
Ma'am, there is 2 type of books of manhattan 5lb, one in green color cover and second in black cover. which one is better. And what to know before taking a book. please tell me.
Hi there! You can see the most current edition of the book here: www.manhattanprep.com/gre/store/gre-strategy-guides/5-pound-book-gre-practice-problems
Thanks for the helpful video, please accept my comment on the way you explained ab>0, bc
good analogy
For the problem around 42 minutes - once you establish that x is negative, why do you need to go on to solve the inequality? Won't you know that x is less than 2 by knowing that x is negative??
Yes, that's totally true! Cat just wanted to solve it out all the way to demonstrate how the math worked. :)
@45:19 how we can take the square root of a negative integer, it is not possible. Even if we take, we will get iota (I) with the integer 2 which is not in the syllabus of GRE. Please clarify if I am wrong.
Hi! We checked with Cat on this and here's what she had to say: "Hi! So I think the way I notated/explained this wasn't as clear as it could be. You're correct that we can't take the square root of a negative integer. Here, though, because I'm working with absolute value, I'm using the squared notation just to think about what x could be in the upfront information (and in that case, x can equal a negative, since we aren't squaring x, but rather multiplying x by the absolute value of x, and then by negative 1.) Apologies that the way I explain that in the video led to confusion!"
Great
for the first problem, I chose a = -1 and b = -1 and the result gave me a positive number. I don't get why it could no be D or A
on the second problem, I solved inequalities as follows:
3x - 21 ≥ 9
+21 +21
3x≥30
/3 /3
x ≥ 10
0.25y - 3 ≤ 1
+3 +3
0.25y ≤ 4
/0.25 /0.25
y ≤ 1
Why is this is this 0.25y ≤ 4 multiplied by 4?
For the equation 0.25y - 3 ≤ 1, your calculation is correct up until the end. 4/0.25= 16. So y ≤ 16
4/.25 or 4/(25/100) or (4*100)/25 =16
you are so cute, here. 🥰
Meticulous lecture . Wearing glass you seem to be changed !
You're really good and very pretty.