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I would like to know how to reduce the following compound proposition to a Conjunctive Normal Form please?

$$(P∨Q)→(R∧(S∧T))$$

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    Hint: Start by replacing $A \rightarrow B$ with $\lnot A \lor B$ – 2017-02-04
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    like this ¬(P∨Q)∨(R∧S∧T)? – 2017-02-04
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    any hint how to do it? – 2017-02-04

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step 1 : replace $A\implies B$ by $\lnot A \lor B$

step 2 : replace $\lnot(A\lor B)$ by $\lnot A\land\lnot B$ and $\lnot(A\land B)$ by $\lnot A\lor\lnot B$

step 3 : use distributivity of $\land$ relatively to $\lor$, that is $(A\land B)\lor C=(A\lor C)\land(B\lor C)$

step 4 : use associativity of $\land$ to remove some superfluous parenthesis

Normally you should get this 3 km long formula...

$(\lnot P\lor R)\land(\lnot Q\lor R)\land (\lnot P\lor S)\land(\lnot Q\lor S)\land (\lnot P\lor T)\land(\lnot Q\lor T)$

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    I'm lost, couldn't get it right yet, can you help? – 2017-02-04