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This is calculated as follows: (2i)2 = 2i x 2i = 4i2 = 4(-1) = -4.
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∙ 13y ago
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What is the imaginary number of square root of -4?
Either 2i or -2i, when squared equal -4.
X2 plus x equals 3x-5?
x2 +x=3x-5 so x2 -2x+5=0 which does not factor ( over the real numbers) so you can either complete the square of use the quadratic equation to solve. Let's complete the square. (x-1)2 =-4 x-1= plus of minus 2i so x=1+2i or x=1-2i Now check it just as you would a real answer. 1+2i -1 is 2i and 2i squared is -4 as desired Now 1-2i-1 is -2i and (-2i) squared is -4 also. We know the answer is not real if we simply calculated the discriminant. b2 -4ac=4-4(5)<0 so there are no real answers as we found.
How can you factor x squared plus 5x plus?
x2 + 5x + not really sure what that extra plus is for... this is the most you can factor it... x(x + 5)
How would you factor x squared plus 4?
(X^2) + 4 = 0(X^2) = -4X = +/- 2i(X+2i)(X-2i)This can't be factorised easily. The above method is the factorisation for (X^2) - 4,and is also the difference of two squares (9-4) = (3+2)(3-2) etc...
What is the conjagate of 6-2i?
It is 6+2i. But -6-2i will also serve.
What is the reciprocal of 2i?
1/2i
What is 2x squared plus 24 equal zero?
so x squared + 12 = 0 so xsquared = -12 which lands you in the realm of imaginary numbers. The square root of -12 is 2i root 3 where i is the imaginary sqrt of -1.
How do you factor x squared plus four x?
You don't, if you're only looking for real number results. If you are including imaginary numbers, x2+4 = (x+2i)*(x-2i).
What is the conjugate of 7 - 2i?
7 + 2i
What is the conjugate of 6-2i?
8
What is the conjugate of 6 minus 2i?
6+2i
What does 7i divided by 2 plus 2i equal?
1.75 + 1.75i7i/2 + 2i = 3.5i + 2i = 5.5i
