Use the properties of complex numbers to simplify the following expression: (square root -25 + 2i) + 5i + ( 9 - square root -36)

1 answer

To simplify the expression \((\sqrt{-25} + 2i) + 5i + (9 - \sqrt{-36})\), we will first express the square roots of the negative numbers using complex numbers.

  1. Simplify \(\sqrt{-25}\):

\[ \sqrt{-25} = \sqrt{25} \cdot \sqrt{-1} = 5i \]

  1. Simplify \(\sqrt{-36}\):

\[ \sqrt{-36} = \sqrt{36} \cdot \sqrt{-1} = 6i \]

Now, substituting these simplifications back into the original expression, we have:

\[ (5i + 2i) + 5i + (9 - 6i) \]

Now, combine the terms:

  1. Combine the \(i\) terms:

\[ 5i + 2i + 5i - 6i = (5 + 2 + 5 - 6)i = 6i \]

  1. The real part is:

\[ 9 \]

Now we can put both the real and the imaginary parts together:

\[ 9 + 6i \]

Thus, the simplified expression is:

\[ \boxed{9 + 6i} \]