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The equation x2 = d has how many real solutions when d > 0?

1 Answer

2 votes

Answer:

Two:
√(d) and
\left(-√(d)\right).

Explanation:

The question is asking for the number of real numbers
x whose square is equal to
d (where
d > 0.)

Naturally, the square root of
d:
√(d) would satisfy the requirement.
\left(√(d)\right)^(2) = d.

However, keep in mind that
(x)^2 and
(-x)^(2) have the same value. Therefore, if
x =√(d) would satisfy the equation, the opposite
x = -√(d) would also do.

Since
d > 0,
√(d) and
\left(-√(d)\right) would both take real values.

Because
d \\e 0, the value of
√(d) and
\left(-√(d)\right) would be distinct.

Hence,
√(d) and
\left(-√(d)\right) would correspond to the two real solutions of this equation.

User Ivan Meredith
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