If ( 1 + tan ) ( 1 + tan ) = 2, then + =


x=0 , y= , z= 0 which represent Y axisWe have 1600=
To form factors we have to do selections from a lot of 2's and 5's and multiply them together.
To form even factor we should choose at least one 2's from the lot , which will ensure that what ever be the remaining selection, their multiplication will always result in an even factor.
The number of ways to select atleast one ‘2’ from a lot of six identical ‘2’s will be 6 (i.e. select 1 or select 2 or select 3 or select 4 or select 5 or select 6)
And, we’ll select any number of ‘5 from a lot of two identical ‘5’s in 3 ways(select 0, select 1,select 2)
There fore the total number of selection of even factors=6x3=18


