# If #x+1/x=-1# then What is the value of #x^247+1/x^187=#?

##### 3 Answers

#### Answer:

#### Explanation:

As already obtained in the first answer,

r = 1.

For the first root, cosine is negative and sine is positive.

the second quadrant and is

For the second, both are negative.

So, it is

Now,

Accordingly,

=2 cos (even

Both are the same -1...

#### Answer:

#### Explanation:

In the equation

Substituting we have

but

so the equation reduces to

Now

and

Putting all together

#### Answer:

-1

#### Explanation:

For lower class student I do it as follows

Given

So

Now

Will this do?