Question

prove tan(A-90)=-cot A

Answer 1

use tan(A-B) formula

Answer 2

tan(A- B)=tanA-tanB/1+tanAtanB

Answer 3

plugin and simplify

Answer 4

okay..i'll try it

Answer 5

good luck :)

Answer 6

knw what, it wont work cuz tan 90 is undefined

Answer 7

we need to break it into sin and cos

Answer 8

il give u a head start

Answer 9

tan(A-90)


sin(A-90)
---------
cos(A-90)

Answer 10

now simply apply sin(A-B) and cos(A-B) formulas

Answer 11

give it a try... :D

Answer 12

oh..okay..now i get it.thanks! :)

Answer 13

glad to hear :)

Answer 14

yw :)