question.... (1 Viewer)

[martin310015]

1. the equation 2x^3-3x^2+x-15=0 has one real zero. by forming a table of values with integral values from x=-3 to x=3, determine the two consecutive integers between which the root lies.

what is a table of values with integral values....thanx

 

[CM_Tutor]

It means draw a table with x values -3, -2, -1, 0, 1, 2, 3, and find the y values in each case, and then find the pair of integer x-values between which the root lies.

 

[:: ck ::]

the two consecutive integers which are subbed into the equation which give opposite signs for the y value, are the integers where the root lies between

 

[martin310015]

ok thanx
yeah and if the the method is not specified what method should i use (halving or newtons) when im just told to approximate a root of a equation with the range the roots are in......eg... 2x^3-x+3=0 in the interval where x is between -2 and -1

 

[CM_Tutor]

I think if it says to use the range the roots are in, the implication is to use halving the interval, but there probably wouldn't be a problem with either approach.

 

[:: ck ::]

it shud specify a method if u need an approximation

but for this q just say a root exists between -2 and -1 or whereever the root lies between

 

[martin310015]

ok thanx