x^2=t >0 and the equation becomes (t-6)^2=2*t so t^2-14t+36=0 and t=(14+ -2* sqrt13)/2. 1st way of writing is x^2=7+ -sqrt13 > 0 BOTH ACCEPTED, so we have FOUR SOLUTIONS x=+sqrt(7+sqrt13) or -sqrt(7+sqrt13) and +sqrt(7-sqrt13) or -sqrt(7-sqrt13). 2nd way is isolating the square root of square root as foliow. 14+ - 2*sqrt13=13+1+ - 2*sqrt13*1=(sqrt13)^2 +1^2 + - 2*sqrt13*1= (sqrt13+ -1)^2 so x=+ - sqrt{(sqrt13+ -1)^2}/sqrt2=+ -Isqrt13+ -1I/sqrt2=+ -(sqrt13+ -1)/sqrt2= + - (sqrt26+ -sqrt2)/2 .Again 4 Solutions.**sqrt(x^2)=IxI=+ -x so sqrt((sqrt13-1)^2)=I sqrt13-1I=sqrt13-1 because sqrt13-1>0**
Делим на х и умножить на 36 (х-6/х-1)^2+(х-6/х+1)^2=6 Легко видно что а=х-6/х Тогда (а+1)^2+(а-1)^2=6 а^2+1=3 а=sqrt 2 или а= - sqrt 2 Дальнейшее просто Два простых квадратных уравнений х-6/х-sqrt2=0 или х-6/х+sqrt 2=0 Решение которых не составит труда Решение от силы 3 - 4 минуты, но не 10 как на видео. Если это часть теста, то вы потеряли 6 минут просто так
No substitution (x²-x-6)²+(x²+x-6)²=6x² (x²+x-6-x²+x+6)²+2(x²+x-6)(x²-x-6)=6x² 4x²+2(x²-4)(x²-9)-6x²=0 ÷2 x⁴-14x²+36=0 ⇒(x²-7)²=13 x=±sqr(7±sqr13) By the way your voice is similar to affrican people You from affrica? My greeting to you
Horrible video. You would have obtained a polynomial of degree 4 and you only found 2 solutions. You cannot disregard the plus or minus sign in this case.
That's a bit harsh. I, too, solved this problem and knew I was looking for four roots. It is easy to get lost in algebra. Although I did not watch the entire video, I did see that he correctly arrived at two of the solutions. Again, we eventually all get lost in the algebra, and I suggest graphing this problem to see that four real roots are present.