Thread: Differentiation Questions

Questions:


How do i do the part




should the angle in be inverse of what it is because answer is (b) and it is only possible when y is some constant which will be using the identity

Some Help please ...

Hello, cupid!


There's something wrong with the problem
. . or it is a "trick question".


. .





Hence, is in a right triangle with:


Since the hypotenuse is the longest side of the right triangle:

. .

. .

The inequality is true only if


Hence: .

Then: .

Hi Soroban
i think you are right but book says that correct answer is (d) None of these

Originally Posted by Soroban

. .

Couldn't you look at it this way:

.

In this case, the inequality would be true if and would essentially result in the domain restriction given in the problem.

When I take the derivative I get . I must go to class now, but will post my work this afternoon if nobody else gets to it first - I'll check my work too (I could be wrong at this point).

Originally Posted by pflo

Couldn't you look at it this way:

.

In this case, the inequality would be true if and would essentially result in the domain restriction given in the problem.

When I take the derivative I get . I must go to class now, but will post my work this afternoon if nobody else gets to it first - I'll check my work too (I could be wrong at this point).

is true only for x=1 as well. Something squared can never be less than zero. . .

Yes, yes. Of course you're right. Perhaps the authors of this problem made the same mistake I did in overlooking this.

No i'm pretty sure that 0 is not the solution.

it may be so for sec-1 term

but sin-1 (acc. to Soroban's post) gives that which is true for all x.