High School Entrance Exam | Only 9% of students got this math question correct

preview_player
Показать описание
What do you think about this question? If you're reading this ❤️. Have a great day!

Hello My Friend ! Welcome to my channel. I really appreciate it!
@higher_mathematics

#maths #math
Рекомендации по теме
Комментарии
Автор

As a person with eyes I solved it and got x = 2 within 10 seconds

Sqrt.Infinity
Автор

x=2 by inspection is one solution. period. This is ridiculous

madelineveggie
Автор

The obvious answer is x = 2. As can be seen, 2^2 = 4 and 4 + 2 = 6. If I rewrite the equation as 2^x + x - 6 = 0, I can plot the equation y = 2^x + x -6 and I quickly see that there is one real root at x = 2 and there is no complex root.

jeanlemire
Автор

I find it hard to believe that high school students are introduced to the Lambert W function.

BartBuzz
Автор

High schools don't have entrance exams. However, 8th graders do learn exponents. So, if a typical 8th grader can't immediately recognize the answer is '2', perhaps the issue is a fundamental flaw in education. And, where does the 9% come from??? Teaching this insanely complex solution to an 8th grader rather than just teaching to employ simple inductive/deductive reasoning will put the child 'off' of math forever. I taught University math and would never abuse college students this way.

arthurmatthewf
Автор

You don't need W for this--however it is good that you explain it, because if you had a problem like 2^x+x=5, now you need W.
Fortunately, the problem here can be factored.
Factor out x for x(2^(x-1)+1=6
Now factor 6 into 2 and 3, guess and check. You find that for 2^(x-1)+1, a value of 2 yields 3--the other factor of 6. So x=2.

fubaralakbar
Автор

OK one trivial solution is x=2.
I'd have to check, whether there are further complex solutions.

Segalmed
Автор

램버트함수 안쓰는문제 제시해줌안되나
며칠에 한번 머리 쓴다생각하고 구독했는데 램버트함수문제 나오면 진이 쏙빠짐
이사람 인도사람임? 그렇지않고서는 자꾸 지수+미지수 문제 내는게 말이안됨
저번에도 램버트문제내서 댓글창 씹창났잖아

안진섭-bw
Автор

Very clever and I enjoyed the practice (even though by inspection x=2 would work nicely on a timed test). That said the Lambert W-Function is very handy and should be in every math major's "tool box".

X
Автор

I liked the second W() trick on the right side of the equation

Roarshark
Автор

This is idiotic and certainly not material for a high school entrance exam.

elloco
Автор

The function is increasing therefore it has almost once solution. If we replace X with 2 and it verifies the equation, we can stop.

vicebubble
Автор

Absurd solution. The obvious answer is 2, easily found in certainly not more than the 10 seconds it took sqrt. You have got to be public sector. No one in the private sector would waste 13 minutes doing something that should take 10 seconds.

davidcarter
Автор

Half way through the exercise, your English accent took a beeline for your native language and became almost incomprehensible.

NothingMaster
Автор

Yeah, great, let's multiply by 2 to the power of 6, but don't ask why.

GeorgeAlexanderOz
Автор

Will you ever stop presenting problems that end in the W function?
Do you think that future high school students EVEN KNOW the W function? (Hint: the answer is NO)

dieterkohler
Автор

This might be the silliest math channel on youtube. The solution is 2 by inspection, no need for the lambert W function, which pre-high school students don't know anyway. Ridiculous.

black_eagle
Автор

Isn’t it obvious that 2 fits the bill?

kosterix
Автор

{2x+2x ➖ }+{x+x➖ }={4x^2+x^2 }=4x^4 (x ➖ 4x+4)

RealQinnMalloryu
Автор

we get, , 2^6=2^2+2^4, 2^2*ln2*e^(ln2)^4, 4*ln2*e^(4*ln2),
, -->, 4*ln2=(6-x)ln2, 4=6-x, x=6-4, x=2,
with W( 2^6*ln2) = 2.772588722, (6-x)*ln2=2.772588722, -->, x=6-2.772588722/ln2, -->, x=2, OK,

prollysine