Which of the following shows an expression equivalent to the product of two complex numbers, 5i • 4i?
41 - 51
9i
20
20i
The expression equivalent to the product of two complex numbers, 5i • 4i, is -20.
To find the product of two complex numbers, you need to multiply both the real parts and the imaginary parts separately.
In this case, the real part of 5i is 0 (since it has no real part), and the imaginary part of 5i is 5.
Similarly, the real part of 4i is 0, and the imaginary part of 4i is 4.
To calculate the product, multiply the real parts and the imaginary parts separately:
Real part: 0 * 0 = 0
Imaginary part: 5 * 4 = 20
So the expression equivalent to the product of 5i • 4i is 20i.
Therefore, the correct answer from the given options is 20i.
To find the product of two complex numbers, you can use the distributive property. In this case, the two complex numbers are 5i and 4i.
The distributive property states that the product of two complex numbers can be found by multiplying the real parts together and the imaginary parts together, and then combining them.
Let's apply this to the given expression: 5i • 4i.
The real part of 5i is 0, and the real part of 4i is also 0. Multiplying these two real parts together gives us 0.
The imaginary part of 5i is 5, and the imaginary part of 4i is 4. Multiplying these two imaginary parts together gives us 20.
So, the product of 5i and 4i is 0 + 20i.
Therefore, the expression equivalent to the product of two complex numbers, 5i • 4i, is 20i, which corresponds to option "20i".