determine the area between x^3+2x and 4x^2-x

Question

anonymous · Answer

i got 10/24 but is wrong??

anonymous · Answer

i also tried 5/12 but wrong too

amistre64 · Answer

well how did you go about trying getting those values?

anonymous · Answer

i found where the intesect which is @ 0 and 1

amistre64 · Answer

given 2 function f and g that intercept as and b; to find the area we integrate

$$\int_{a}^{b} f-g~dx$$

anonymous · Answer

then i set up the integral problem
found the antiderivatives which i found to be
(.25x^4 + x^2) - (4/3x^3 - .5x^2)

anonymous · Answer

thats what i did but i dont know where i went wrong

amistre64 · Answer

$$\int_{0}^{1} (x^3+2x)-(4x^2-x)~dx$$

anonymous · Answer

when i plug in the values thats what i got

amistre64 · Answer

the zero is useless sooo this ends up as$$\frac14+1-(\frac43-\frac12)$$

right?

anonymous · Answer

correct! thats what i got

anonymous · Answer

so can i not add fractions right? 
isnt is (5/4) - (5/6)?

anonymous · Answer

which is 10/24?

amistre64 · Answer

.4166666......  or 5/12

lets check the interval to be sure

anonymous · Answer

and i got 5/12 by distributing the negative so it is (5/4) - (11/6)

anonymous · Answer

my website homework says 5/12 is wrong

amistre64 · Answer

youre missing it at x=3

amistre64 · Answer

you need to integrate it again from 1 to 3

anonymous · Answer

oooooooo

anonymous · Answer

so the value of one is 5/12

anonymous · Answer

i got to find the value at 3

amistre64 · Answer

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