# Math Help - Checkers

1. ## Checkers

I was wondering if someone can check my work on these 2 problems about integrals.

A) the integrals from -2 to 3 (25)^2x+1 dx
the answer i got was [25^(7) / 2ln(25)] / [25^(-1) /2ln(25)]

B) the ingtegral 7x 6^(1-2x^2) dx
the answer i got was (-7/4) [6^1-x^2] / [4ln(6)] + C

thanks for the help

2. Originally Posted by uniquereason81
I was wondering if someone can check my work on these 2 problems about integrals.

A) the integrals from -2 to 3 (25)^2x+1 dx
the answer i got was [25^(7) / 2ln(25)] / [25^(-1) /2ln(25)]
Use more brackets to make the integrand unabiguous.

Why have you not simplified this? It looks like it simplifies to 25^8 to me.

Your integrand is bounded above by 25^7 and is over an interval of length 5 so an upper bound on the integral is 5x25^7<25^8.

This integral look to be ~=25^6.4 to me.

CB