Boolean Expressions Practice

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Evaluate the follwing boolean expressions, given the following declarations and assignments. Answers

boolean p = true;
boolean q = false;
boolean r = false;
boolean s;

int i = 10;
int j = 12;
int k = 15;
int l;

1)	p && q || r

2)	!q || p && r

3)	--i * i + j * j == k * k

4)	!(p && q) || (p && r)

5)	(!p || q) && (!q || p)

6)	q || r || p || s

7)	-i > -j || (s && !s || s)

8)	!(q && r) && (q && p) || (p && r) && !(s && p)

9)	++i == --j

10)	p && i <= k || !(s && p)

11)	r || !r && --k % j >= j % i

12)	!(p && (!p || s)) || s

13)	!(!s && (!p || s)) || p

14)	i < l || i == l || i > l

For what (combination of) values of the primitives do the following expressions evaluate to true? Wherever unspecified, you may assume that p, q, r, and s are boolean primitives and that i and j are int primitives. Answers

15)	p || !q

16)	5 <= i && i < 8

17)	5 <= i && i < 8		where i is a double

18)	p && q && !p

19)	3 < j && 8 >= j && 6 != j

20)	p && q && !r || !p && r

21)	(p || q || !r) && (!p || r)

22)	p && (!p || q) && (!q || r) && !r

23)	!(p != false && p == q) || q != false

24)	p == true && !(p && !q) && q != (r || !r && s || !s)

Which of the following expressions are equivalent? Answers

25)	a.	p && !q || !p && q
	b.	!(p && q)
	c.	(p || q) && (!p || !q)
	d.	!p || !q

26)	a.	!(p || q)
	b.	p && q || !p && !q
	c.	(!p || q) && (p || !q)
	d.	!p && !q

27)	a.	p || !q
	b.	p && q || !q
	c.	p || !p && !q
	d.	p && q || p && !q || !p && !q