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Q. Consider the integral $I =\int_1^{ e }(\cos (\ln x )+\sin (-\ln x )) dx$
Statement-1: $I=e \cos (1)-1$
Statement-2: $\int\limits_a^b\left(f(x)+x f^{\prime}(x)\right) d x=b f(b)+a f(a)$

Integrals

Solution:

If $f ( x )=\cos (\ln x )$, then $x f ^{\prime}( x )=\sin (-\ln x )$
Statement-1 is true, statement-2 is false