Question

TAN 4A +TAN9A +TAN4A TAN9A TAN13A=TAN13A

Answer 1

Answer:

follow

Prove that:

tan13A-tan9A tan4A=tan13Atan9Atan4A

For this equation we will use the formula:

i) tan 2a= tan(a + a) and,

ii)tan (a + b)= (tan a+ tan b)/(1-tan a tan b)

From (i), we can say

tan 13A= tan (9A+4A)

but, tan(9A+4A)=(tan 9A + tan 4A)/ (1-tan 9Atan 4A)

Therefore tan13A=(tan 9A+tan4A)/(1-tan9Atan4A)

=tan13A-tan13Atan9Atan4A=tan 9A+tan 4A

therefore,

tan13A-tan9A-tan4A=tan13Atan9Atan4A

tan13A=tan9A+tan4A+tan13Atan9Atan4A

hope this have helped you out

please do follow me and Mark me as a brainliest