Question

conclusion of valid deductive argument is always certain​

Answer 1

Yes a valid deductive argument makes the conclusion certain and specific( that is, either true or false)

because a deductive argument is valid only if the premises are true, the conclusion should , without fail, be true and vice versa

An Example of a valid deductive argument

Premise 1: If Jim is a rabbit, then surely it is a mammal

Premise 2: Jim is a rabbit

Conclusion: Therefore, Jim is mammal

In this case there are only 2 possibilities for the conclusion, either Jim is a mammal or not a mammal, depending upon the truth function of the premises( either true or false)

so conclusion is certain.....

Hope its clear!