View all: BANGLADESH DEVELOPMENT BANK LTD (SO) WRITTEN QUESTION (MATH) SOLVE | 2018
Correct Answer: ${0\le x\lt \frac{5}{3}} or, x\gt 10$
Explanation:
Here, p = 3x$^{2}$-35x+50
Now. if the company makes a profit
p >0=> 35$^{2}$ + 50 > o
=> 3x$^{2}$ -30x – 5x + 50 > 0
=> 3x(x- IO) – 5(x – l0) >0………………………………….(i)
As this equation (i) is greater than 0. so the value of the two roots must have different values in different intervals.
Now . front the equation (i), we have, The value of x is greater than 10 . So x > 10
0r. the value of x is less than $\frac{5}{3}$ and greater tlum or equal to 0 i.e. 0 $\le x\lt \frac{5}{3}$
because advertising cost can not be negative.
So. if the company makes a prof it. the values of x is
$ {0\le x\lt \frac{5}{3}} or, x\gt 10 $ |