A giant star is a star with substantially larger radius and luminosity than a main-sequence (or dwarf) star of the same surface temperature. They lie above the main sequence (luminosity class V in the Yerkes spectral classification) on the Hertzsprung–Russell diagram and correspond to luminosity classes II and III.
A = √(15²-9²) = √(225-81) = √144 = 12
The expression which is equivalent to √(-9) is 3i.
<h3>What is Complex number?</h3>
A complex number is the sum of a real number and an imaginary number. A complex number is of the form a + ib and is usually represented by z.
Here, given expression;
y = √(-9)
y = √9 X √(-1)
y = 3√(-1)
y = 3i
Thus, the expression which is equivalent to √(-9) is 3i.
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Answer:
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