A.(p→q)一定為假B.(q→r)一定為假C.(p→r)一定為假D.(p→s)一定為假
A.((A∨B)∧(C∨D)∧(E∨F))B.((A∧B)∨(C∧D)∨(E∧F))C.((A→B)∨(C→∨(E→F))D.((A→B)∧(C→D)∧(E→F))
A.((A∧B∧C∧D∧E∧F∧G∧H∧I)→(J∧K∧L∧M)B.((A∧B∧C∧D∧E∧F∧G∧H∧I)→((J∧K∧L)→M))C.(((A∧B∧C∧D∧E∧F∧G∧H∧I)→(J∧K∧L))→M)D.(((A∧B∧C∧D∧E∧F∧G∧H∧I)→(J∨K∨L))→M)