Here's the question you clicked on:
strawberry_militia
P(x)=\[x^4-x^3-7x^2+x+6\] Solve P(x)>0
simplify the equation into its factors one factor being x-1 and find other factors then write down the domain of the factors, and you'll see the range is positive in certain domain that's the answer
factorise it and find zeros and use tabe
table method not tabe
@sauravshakya what is the table method?
table method: sit down at the table with pencil and paper :)
I will do for easy one ok suppose |dw:1344005362435:dw|
can you find the zeros then use synthetic division to reduce it to a smaller factor?
here |dw:1344005426187:dw|
can you use calculus?
x^4 + .... has the shape|dw:1344005576425:dw| knowing the min and max parts would be useful
|dw:1344005474076:dw| now using table |dw:1344005508829:dw|
so from the table we get|dw:1344005614786:dw|
got it @strawberry_militia
use this similar method to solve your question @strawberry_militia
well, a quick trial and error gives me one zero: f(0) = 6 f(1) = 0
that should reduce it to a cubic
I have found the factors.
then plot them on a number line and take test point between the zeros to determine signage
write down the factors in coordinates form like if the four factors are a,b,c,d and a<b<c<d then write it as (-infinity,a) (a,b) (b,c) and (c,d)
to -inf and +inf should be positive just by the nature of the poly
and (d,infinity) then substitute a value in between (-infinity ,a) and check it is positive or not similiarly do for (a,b) (b,c) and (c,d) and (d,infinity)
so when you get a positive value..that is your required range
I will try it out. thanks for all your responses.