Another e integration: xe^(-x^2)

x times e to the negative x squared

+∞
  ∫  x · e ^(-x² ) dx =   /  The substitution:  u = - x²,  x d x = - du / 2  
-∞
                                                              +∞
= - 1/2 ·  ∫ e ^(u)  du  = - 1/2 · e ^(-x²)  /
                                                             - ∞
e^(-∞) = 1 / e^(∞)

= -1/2 · [ 1/ e^(∞) - 1/ e^(∞) ]  = -1/2 · ( 0 - 0 ) = 0

I'll do the first one for you. it isn't very hard at all.on number one, you have (50 × 3), which equals 150, and (3 × 3), which equals 9. after you establish that, you add 150 and 9 together. so, (150 + 9) equals 159.this means that 53 × 3 = 159.