SOLUTION: Can you solve this, (2x^3-5x+40)÷(2x+1) using long division? Thanks a lot.

Algebra.Com
Question 1178741: Can you solve this, (2x^3-5x+40)÷(2x+1) using long division? Thanks a lot.
Found 2 solutions by josgarithmetic, Theo:
Answer by josgarithmetic(39617)   (Show Source): You can put this solution on YOUR website!
             x^2
        _________________________________________
 2x+1   |   2x^3    0x^2    -5x     40
        |
        |   2x^3     x^2
        ----------------
            0      -x^2    -5x



This is NOT yet finished. Can you see how to continue?

Answer by Theo(13342)   (Show Source): You can put this solution on YOUR website!
this one is a little difficult to follow, but i think i got it right.

my worksheet is shown below.

first one does the division.
second one check to see that the division was done correctly.
in the division section:

step 1 just puts the division into long division format.
any missing exponential terms in the dividend are inserted as 0 * that term.
the missing term in the dividend was x^2, so a + 0x^2 was inserted.
it can be done without doing this, but inserting the missing terms makes the division a little clearer.

step 2 divides the first term in the dividend by the first term in the divisor to get 2x^3 / 2x = x^2.
x^2 is placed in the quotient area.
the whole dividend is multiplied y x^2 and then subtracted from 2x^3 + 0x^2.

the result of the subtraction is in step 3 and the rest of the dividend is brought down as well.

step 4 divides the first term in the result of step 3 by the first term in the divisor to get -x^2 / 2x = -.5x
the -.5x is brought up into the quotient area.
the whole divisor is then multiplied by -.5x to get -x^2 - .5x.
that is then subtracted froom -x^2 - 5x + 40.

step 5 shows the results of the subtraction.
the remaining term from step 3 is brought down as well.

step 6 divides the first term from step 5 by the first term in the divisor to get -4.5x / 2x = -2.25.
the -2.25 is brought up to the quotient area.
the whole divisor is then multiplied by -2.25 to get -4.5x - 2.25 which is then subtracted from the result in step 5.

step 7 shows the result of the subtraction.
since the largest term in step 7 is less than the largest term in the divisor, the division stops and that is the remainder.



the check section:

step one sets up the multiplication of the quotient and the divisor.

step 2 shows the multiplication being performed.

step 3 shows the result of the multiplication.
then the remainder is added.

step 4 shows the result of the multiplication with the remainder added.
since the result is the original equation of the dividend, the division was performed correctly.



here's a reference on long division you might find helpful.

https://www.purplemath.com/modules/polydiv2.htm

that same reference links to examples you might also find useful.

https://www.purplemath.com/modules/polydiv3.htm


RELATED QUESTIONS

how do I divide polynomial (2x^3-5x+40)÷(2x+1) using long division.... (answered by ikleyn)
how will you solve this eaple using synthetic division 2x^3+5x^2-4x-1/x^2-1 (answered by Edwin McCravy)
Algebra help with a long division problem? Solve with synthetic division. {{{ (2x^4 -... (answered by josgarithmetic)
Divide using long division: (4x^4-5x^3+2x^2-x+5) ÷... (answered by It is costly)
how d you solve (x^3+4x^2-5x+1) / (x+3) using long division (answered by solver91311)
solve using long division, then check.... (answered by lwsshak3)
Can someone please help me in solving this problem. Thanks. Use long division to reduce (answered by xcentaur)
can someone help me with this please (1/2x-10)(1/2x+10) thanks a... (answered by checkley75)
Please help me solve this polynomial long division problem: (2x-3)/(2x^3-9x^2+13x-6) (answered by scott8148)