Trignometry Exact Ratios problem (1 Viewer)

[kevinsta]

im stuck on this problem because the answer i get isnt what its suppose to be

Evaluate: tan45 + tan60 over 1-tan45 x tan60

 

[rumbleroar]

tan 45 = 1
tan 60 = rt 3

rationalise the denominator

what steps are you having trouble with?

 

[kevinsta]

tan 45 = 1
tan 60 = rt 3

rationalise the denominator

what steps are you having trouble with?

when i expand i get 1+ rt3 over 1-1x rt3 dont know what to do next

 

[Shadowdude]

when i expand i get 1+ rt3 over 1-1x rt3 dont know what to do next

 

[kevinsta]

I got lost when you times it by 1+ Rt 3 for both sides arent you suppose to times it by 1- rt 3 on both sides? and what did you do for the result to get it into -2 -rt 3 form

 

[Shadowdude]

I got lost when you times it by 1+ Rt 3 for both sides arent you suppose to times it by 1- rt 3 on both sides? and what did you do for the result to get it into -2 -rt 3 form

If you multiply by 1-sqrt(3), you don't simplify the denominator.

Also I evaluated the fraction.

 

[kevinsta]

If you multiply by 1-sqrt(3), you don't simplify the denominator.

Also I evaluated the fraction.

why arent u suppose to simplify the denominator?

 

[Audranda]

Shadowdude multiplied it by 1 + sqrt(3) to rationalise the denominator (to remove the sqrt) - also known as the conjugate (the overall conjugate= 1).

 

[kevinsta]

Shadowdude multiplied it by 1 + sqrt(3) to rationalise the denominator (to remove the sqrt) - also known as the conjugate (the overall conjugate= 1).

you couldve got rid of the squart by multiplying it by 1 - sqrt(3), i thought when trying to get rid of the root your suppose to times it by the denominator

 

[Shadowdude]

why arent u suppose to simplify the denominator?

You're supposed to.

you couldve got rid of the squart by multiplying it by 1 - sqrt(3), i thought when trying to get rid of the root your suppose to times it by the denominator

No, the conjugate of the denominator. If you multiply it by the denominator, you won't be able to simplify the fraction - try it yourself.