1.
2
∫ x^3 - x dx (i expanded the orginal equation)
-1
= [x^4/4 - x^2/2]
= [4 - 2] - [1/4 - 1/2]
= 4 1/4 sq. units
hmm...my answer is diff from urs...maybe i got it wrong...
2. for this question...it wud rili help if u draw the graph first
for the equation... when y= 0, x = 0, 1...
yep...i did use cos x=
1 - t^2
1 + t^2
using that i came up with this....
2∫ 1 - t^2 dt
(1 + 3t^2)(1+t^2)
kinda stuck wid that at the moment....any hints to continue wid that?
whoops...pressed sumthing... newayz to continue...
Testing n = 1
LHS = 1
RHS = 1/6 x 1 x (1+1)x(2+1)
= 1
...therefore true for n=1
let n=K
1^2+2^2+...k^2 = 1/6 k (k+1)(2k+1)
show the result is true for n=k+1
1^2+2^2...k^2+(k+1)^2 = 1/6 (k+1)(k+2)(2k+3)
LHS = 1/6 k...