hards methods i mean specialist :D questions

[hard]

Your first step is incorrect. By stating , you're adding another answer in which is why you have the

Try this:

I would be very careful factoring that square root of -1



as you can see, it's not exactly the 'right' thing to do in surds

what 'should' be done is

so this would be the correct way to do it?


so instead of putting
you'd put and then expand to make it equal -1?

[shinny]

Your first step is incorrect. By stating , you're adding another answer in which is why you have the

Try this:

I would be very careful factoring that square root of -1



as you can see, it's not exactly the 'right' thing to do in surds

what 'should' be done is

Ah right didn't think of it that way. Normally I wouldn't write it like that but it seemed to explain things clearer in doing so.

so this would be the correct way to do it?


so instead of putting
you'd put and then expand to make it equal -1?

Just do exactly what Mao did. Don't split it up, but rather convert the negative (implied -1) inside the original surd, into

[hard]

okay the question asks:

Evaluate x ³ + 2 x ⁴ + +

So far this is what i have done:

x ³ + 2 x ⁴ + +

= x ²)i + 2 x ²)² + +

= x + 2 x 1 + +

=( + ) + ( + +   )

= + + + +  

= + /

okay so after this i'm stuck; but not 100% sure i did it right.

the asnwer says but not sure how they got that?

can someone shed some light.

[Glockmeister]

Is the Re and Im in the question. cause if it is, then there will be no imaginary number.

[hard]

Is the Re and Im in the question. cause if it is, then there will be no imaginary number.

yer it's part of the question but what do you mean there will be no imaginary number. How so?

[shinny]

Because you remove the 'i' when you take the imaginary part of something. e.g. and in that case, the book's answer is definitely wrong.

[hard]

Because you remove the 'i' when you take the imaginary part of something. e.g. and in that case, the book's answer is definitely wrong.

so how would you do the question

[hard]

??

[Glockmeister]

When you say Re(z), you are basically saying that this is the co-efficient of the 'real' part of a complex number z. In the same manner, Im(z) refers to the co-efficient of the 'imaginary' part of a complex number z.

[shinny]

Due to cbf, I'll just show the main steps and skip the algebra hacking.











To do the dividing in the first few steps, just multiply top and bottom by i to 'realise' the denominator.

[hard]

Due to cbf, I'll just show the main steps and skip the algebra hacking.











To do the dividing in the first few steps, just multiply top and bottom by i to 'realise' the denominator.

thanx