Local cohomology killed by a power of I

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Notations:: $H^i_I(M)$ is $i^{th}$ local cohomology of $M$ with support in $I$ and $H^i_I(M)=R^i\Gamma_I(M)$ where $R^i\Gamma_I(M)$ is the right derived functor of a covariant left exact functor, where $\Gamma_I(M)=\{m\in M \mid I^nm=0 \text{ for some }n\}$.

Suppose every element of $M$ is killed by a power of $I$.

Claim:: $H^0_I(M)$ = $M$ and $H^i_I(M)=0$ for $i > 0$.

$H^0_I(M)$ = $M$ is clear from definition

Please do not assume direct limit definition of local cohomology

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Local Cohomology An Algebraic Introduction with Geometric Applications by BRODMANN -SHARP
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