This is the proof to the first Math Proof Problem of the Week.

**Proof **

Squaring results to

Now, since.

Since ,

.

This means that

Now, since , is positive, which means that

is positive.

Therefore,

This is the proof to the first Math Proof Problem of the Week.

**Proof **

Squaring results to

Now, since.

Since ,

.

This means that

Now, since , is positive, which means that

is positive.

Therefore,

hai, may i know how to prove the (-1)(-1)=1 in mathematics?

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I’ll have to check my solution and see if it is longer or shorter or about the same.