8 Answers
oh nice....
Just think how many times y=2x+3x+4x
and y=5x
their derivatives will help which one is increasing at what rate...
Also plotting some imp points will help.......
If this does not help....Plz tell.....
answer is 1 solution on substituting 1 2 and 3 you get
on substitutong 1 : 9 on lhs and 5 on rhs
on substitutong 2 : 29 on lhs 25 on rhs
on substitutong 3 : 99 and 125
in first 2 cases lhs > rhs
3 case lhs<rhs
clearly the graphs will intersect in this region and never intersect again.
(between substituting 2 and 3)
the ans is 1 sol.
i did it by takinh 5x to the rhs and then divided the whole expression .by 5x
yes naman.. that is a good way too :)
I would say a much better way
but i am not sure whether (2/5)x+(3/5)x+(4/5)x will have graph similar to ax.
it will be the sum of these three.. and u have to check the derivatives to see the behaviour.. i am sure it wont be such a difficult ask!
and btw graphs is used to find some short cut.. so it gives u a much faster way to solve..