7.1 Integration By Parts/33

$\int (cos{\sqrt {x}})dx$ = $2{\sqrt {x}}\int (cosu)du$ = Failed to parse (syntax error): {\displaystyle \2int(u)(cosu)du}

${u}$ = ${\sqrt {x}}$

${du}$ = ${\frac {1}{2{\sqrt {x}}}}dx$

$2{\sqrt {x}}{du}$ = ${dx}$