1:24 "50% of you ... the answer is two. ... You get 50% credit" (Assumed you are using that sqrt sign (√) in a task in the same way as you are using it in this video.) If one of your students says sqrt(4)=2 then he/she is **fully** right and you are wrong by saying otherwise: The expression sqrt(4) is defined as the **principal** square root of 4 (the nonnegative square root of 4), which indeed is 2 (and never -2). There is no math symbol for a common branch of a root - using the symbol "sqrt()" (√) always means the principal branch of the (square, cube, ...n-th) root. If you want to ask for (all) the common branch(es) of square roots, then you have to avoid that math symbol "sqrt" (√); example: Solve "r^2 = 4" for r. (Answer: r=+/-2). 5:37 "This is actually the most correct way to write this." No, it is just an incorrect way to write this; a correct answer were "4^(1/2)=+/-2" (4 to the power of 0.5). Sidenotes: In my experience the number one source of confusion on that topic is the invalid use of the math symbols by teachers, so the students have to guess what the teacher might mean. Usage of expressions like +/-sqrt(2) would be meaningless if sqrt(2) would also provide +/-.
sqrt (4) = POSITIVE 2 not negative two. y = sqrt(x) for x > 0 only gives positive values for y. sqrt(x) is always POSITIVE for all positive values of x. Try graphing y = sqrt(x). I think you are getting confused. If x^2 = 4 then x = +/- sqrt(4) fully correct so x = + sqrt(4) or x = - sqrt(4) so x = +2 or x = -2 note: sqrt(4) is positive only if x^2 = 4 then x = sqrt(4) is only half the answer and sqrt(4) = +/- 2 is incorrect
It is amazing to see video titled "Reasons Students fails square root questions" which itself completely fails to understand the square root. √4 = 2 not ±2 √-4 = 2i not ±2i
I appreciate the time and effort you put into teaching math, but this in particular lesson, you are WRONG! Many of the comments explain why. If you don’t agree with these perhaps you should review your tutorial, “99% of Math Students Get This STEP CONFUSED!”. They maybe getting the step confused because of the instruction provided here.
Sqr 4 is also (10-8)x(10-8), but why would that be a required answer unless specified? Can't see how negative numbers have any practical application either. They are not whole numbers, just a derivation. What is the sqr of -4 btw?
#1 Reason the creator of this video FAILS Square Root Questions: They don't understand what the principal square root is and don't understand that √4 is not ±2
You owe so many students so many points. The square root of x is usually defined to = y if y squared = x AND y is > or = to zero. How else could there be a square root function? Why would we write plus or minus in front of any square root if it already meant plus or minus, according to you. By the way, the square root of x squared is ...the absolute value of x. That's what brings in the plus or minus when solving.
I work in the petrochemical industry for 20 years witch relies heavily on engineering math and i can tell you in no real world environment would your math ever work or result in a correct answer to a real design or engineering problems!
Chief……love your work…….hey you are saying because it is x^2 it has two solutions…….if it is x^3 does it have three solutions…..I am poor can you tell me what this is called or if you have a yt video covering this…….god bless
@@pyotrleflegin7255 Thanks for saying that. Even I, who was denied the possibility of learning mathematics in school because the teachers were too arrogant to explain anything based on practical examples, say so - and have been attacked verbally several times for saying so, by people who believe they are great at mathematics.
I am learning math and I just want the facts, not a long talk about making mistakes. In fact the more people go on about making errors the more confusion they generate. So ... square root of 4 is +2 or -2. Sorted.
I never considered the two values of a square root before! wow! great video, thank you for introducing that concept to me!
You went to the wrong school 🚸
Christopher Ellis lol im still in yr 6 :')
1:24 "50% of you ... the answer is two. ... You get 50% credit"
(Assumed you are using that sqrt sign (√) in a task in the same way as you are using it in this video.)
If one of your students says sqrt(4)=2 then he/she is **fully** right and you are wrong by saying otherwise:
The expression sqrt(4) is defined as the **principal** square root of 4 (the nonnegative square root of 4), which indeed is 2 (and never -2).
There is no math symbol for a common branch of a root - using the symbol "sqrt()" (√) always means the principal branch of the (square, cube, ...n-th) root.
If you want to ask for (all) the common branch(es) of square roots, then you have to avoid that math symbol "sqrt" (√); example:
Solve "r^2 = 4" for r.
(Answer: r=+/-2).
5:37 "This is actually the most correct way to write this."
No, it is just an incorrect way to write this; a correct answer were "4^(1/2)=+/-2" (4 to the power of 0.5).
Sidenotes:
In my experience the number one source of confusion on that topic is the invalid use of the math symbols by teachers, so the students have to guess what the teacher might mean.
Usage of expressions like +/-sqrt(2) would be meaningless if sqrt(2) would also provide +/-.
I took calculus 4 in college about 20 years ago. I really have to brush up my on my preciseness. Thanks
Your confusing the crap out of me sir.
Being a dyslexic I have I no idea what you are doing.
sqrt (4) = POSITIVE 2 not negative two. y = sqrt(x) for x > 0 only gives positive values for y.
sqrt(x) is always POSITIVE for all positive values of x. Try graphing y = sqrt(x).
I think you are getting confused.
If x^2 = 4
then x = +/- sqrt(4) fully correct
so x = + sqrt(4) or x = - sqrt(4)
so x = +2 or x = -2 note: sqrt(4) is positive only
if x^2 = 4
then x = sqrt(4) is only half the answer
and sqrt(4) = +/- 2 is incorrect
This is why math sucks and everyone fails it, because there are to many rules and they always change for every question that are the same.
Some people can't understand clear easy rules I guess.
It is amazing to see video titled "Reasons Students fails square root questions" which itself completely fails to understand the square root.
√4 = 2 not ±2
√-4 = 2i not ±2i
I appreciate the time and effort you put into teaching math, but this in particular lesson, you are WRONG! Many of the comments explain why. If you don’t agree with these perhaps you should review your tutorial, “99% of Math Students Get This STEP CONFUSED!”. They maybe getting the step confused because of the instruction provided here.
Sqr 4 is also (10-8)x(10-8), but why would that be a required answer unless specified? Can't see how negative numbers have any practical application either. They are not whole numbers, just a derivation. What is the sqr of -4 btw?
#1 Reason the creator of this video FAILS Square Root Questions:
They don't understand what the principal square root is and don't understand that √4 is not ±2
You owe so many students so many points. The square root of x is usually defined to = y if y squared = x AND y is > or = to zero. How else could there be a square root function? Why would we write plus or minus in front of any square root if it already meant plus or minus, according to you. By the way, the square root of x squared is ...the absolute value of x. That's what brings in the plus or minus when solving.
So what’s the answer ? You went from 4 to 2 to 2i where did the i come from ?
This is so wrong. I feel bad for students going to this video for help.
I didnt learn any
I am so confused but it is so clear. Thanks for helping me out with this! I'm only in elementary. Wow!
Good job! Just to Point sth at 03:17 .It's incorrect to write sqrt(16)=□ • □=16 .
I work in the petrochemical industry for 20 years witch relies heavily on engineering math and i can tell you in no real world environment would your math ever work or result in a correct answer to a real design or engineering problems!
I know nothing about engineering but that was also my opinion
ALGEBRA AND SQUARE ROOTS ARE MARVELOUS .. THANK YOU VERY MUCH SIR
Chief……love your work…….hey you are saying because it is x^2 it has two solutions…….if it is x^3 does it have three solutions…..I am poor can you tell me what this is called or if you have a yt video covering this…….god bless
Thank you for this. I'm studying for the IBEW test and your videos are helping immensely!
Thank you!
I said two, reason being four is a perfect square
Why does -2^-2= .25 and -2^-3= .125, but the sqr of .25= .5?
sqrt (-4) = error
The issue is that is now how they taught when i was in school. It makes if far more confusing .
THANKS SIR ,....YOUR MATERMATICS IS AWESOME ... CLEAR UNDERSTANDING
That helps a lot!!!! Thanks!
Thank you 😊👋😊👋😊👋😊👋
more please
Please Hindi mein bataiye 🙏🙏🙏🙏🙏
8.11 4 x -1= -4
4x = -3
X= -3/4
The answer is an opinion.
In a way, all maths is a convention. As long as we all agree on the conventions, it works well enough!
Pyotr Leflegin like the Dollar.
@@pyotrleflegin7255 Thanks for saying that. Even I, who was denied the possibility of learning mathematics in school because the teachers were too arrogant to explain anything based on practical examples, say so - and have been attacked verbally several times for saying so, by people who believe they are great at mathematics.
I am learning math and I just want the facts, not a long talk about making mistakes. In fact the more people go on about making errors the more confusion they generate. So ... square root of 4 is +2 or -2. Sorted.
No not sorted because √4 = 2 not ±2. The maker of the video doesn't understand this basic mathematics.
sqrt (-4) = invalid input
👍👍👍
You are the 1st!!!