Solution:

Given, 7€ i=4√2i -1

To write in the standard form a+bi, we need to separate the real part and imaginary part.

Real part = 4√2i -1

Imaginary part = 7€ i

Real Part:

Let's convert 4√2i to the standard form.

4√2i = 4i√2

= 4√2 * i

= 4 * √2 * i

Now, the real part = 4 * √2 and the imaginary part = 4i

Therefore, Real part = 4 * √2 - 1

Imaginary Part:

The imaginary part is already in the standard form.

Imaginary part = 7€ i

Putting both parts together, we get:

7€ i = 4 * √2i + (7€ i) - 4 * √2

= -4 * √2 + 7€ i

Hence, the given expression 7€ i=4√2i -1 can be written as:

7€ i = -4 * √2 + 7€ i

or

-4 * √2 + 7€ i

Note: The Euro sign (€) is used in the given expression instead of the usual currency sign for the euro (€).

Option (a) is the right answer