7. Given the integral: (' cosh ( 32 ) dx Jo Sinh ( 30) We are not able to integrate this problem directly. However, a u-sub will make this problem doable . a . Give a paragraph explanation for why us sinh (3 x ) is the correct u- sub . b. There are other natural u-sub to try as well. However they would end up not helping us. Explain why u= cosh ( 320 ) and u = sinh (3x) would not be the connect u-sub here