(1)^1/3=?
I know simple, but can't think right now
im pretty sure it would be 1!
I was thinking 1/3 but not quite sure
nope lol can you try 1 then let me know because i took (1)^1/3 and i got 1 after i typed it in my calculator
On my last try, My calculator computes .333333 aka 1/3. try parenthesis around the one and then make sure you are placing 1/3 as a power/exponent outside the parenthesis
ok hold on lol
ok nevermind i got 1/3. this time lol
ok just making sure, how r u at trig?
yupp and ummm... it depends what the problem is lol
depends on what class you are taking if you are using real numbers then \[1^{\frac{1}{3}}=\sqrt[3]{1}=1\]
if you are living in the world of complex numbers, then there are three "cube roots" of one
complex
i'll display the whole problem
on of them is 1 the other two are \(-\frac{1}{2}+\frac{\sqrt{3}}{2}i\) and its conjugate \(-\frac{1}{2}-\frac{\sqrt{3}}{2}i\)
Solve the equation. (List your answers counterclockwise about the origin starting at the positive real axis. Express θ in radians.) z3 − 1 = 0
there are a couple ways to find the other two. from algebra you can solve \[x^3=1\] \[x^3-1=0\] \[(x-1)(x^2+x+1)=0\] and use the quadratic formula for \(x^2+x+1=0\)
or you can use trig
or you can just look with your eyes at the unit circle divided in two three parts with one of the parts at 1 |dw:1355147845893:dw|
Its trig, using unit circle pi/3, pi, 5pi/3
no it would not be those it would be the ones on the picture above the angles are \(\theta=0,\theta=\frac{2\pi}{3},\theta=\frac{4\pi}{3}\)
you can check it is right using the quadratic formula, but we can work through the trig slowly if you like
the radius would b? the equation will be in this format, r(cos \[r(\cos \theta + isin \theta) ____ z ^{3}-1=0 _____ z ^{3}=1\]
ok i got it
the radius is 1
because you are trying to solve \(z^3=1\)
\[\sqrt[3]{z}= 1^{\frac{ 1 }{ 3 }} _____ 1/3(\cos \pi/3+isin \pi/3)\]
lets go slow, i sense there is some confusion about what you are trying to solve and how you write a number in trig form
the \(\frac{1}{3}\) is in the exponent, it is not a coefficient
your job is to solve \(z^3=1\) in the complex plane, i.e. your job is to find the three cube roots of one we can write 1 as a complex number in the form of \(1=\cos(0)+i\sin(0)\) which is a rather silly thing to do but it has it uses we know this because \(\cos(0)=1\) and \(\sin(0)=0\) so this just says \(1=1+0i\)
to find the cube root, divide the angle by 3 and take the cube root of \(r\) which is in this case its 1 but zero divided by 3 is just zero, and the cube root of one is just one so again you get \[\cos(0)+i\sin(0)=1\] which you already knew, since it is clear that \(1^3=1\) the real job it to find the other two cubed roots of one
if you go around the unit circle again, you go from \(0\) to \(2\pi\) and so you can write \[1=\cos(2\pi)+i\sin(2\pi)\] now again divide the angle by 3 for the next cubed root of 1 and get \[\cos(\frac{2\pi}{3})+i\sin(\frac{2\pi}{3})\]
when you evaluate the trig functions you get \[\cos(\frac{2\pi}{3})+i\sin(\frac{2\pi}{3})=-\frac{1}{2}+\frac{\sqrt{3}}{2}i\]
let me know when i have lost you
got u its becoming clearer
Thank u so much
then if you go around the unit circle one more time, you get \[1=\cos(4\pi)+i\sin(4\pi)\] divide by 3 get \[\cos(\frac{4\pi}{3})+i\sin(\frac{4\pi}{3})\]
it is really much easier to visualize dividing the unit circle in to three parts see the picture above
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