1. 6
2. 7
3. 14
4. 21
21
1. -1
2. -2
3. 1
4. 2
1
1. 0
2. 2
3. 54
4. 120
0
1. cos-1(4/21)
2. sin-1(4/21)
3. cos-1(1/4)
4. cos-1(3/4)
cos<sup>-1</sup>(4/21)
1. 3/2
2. -3/2
3. 0
4. 2[a b c]
-3/2
1. π/3
2. π/4
3. π/6
4. π/2
π/2
1. √224
2. √300
3. √254
4. 18
18
1. -2
2. 2
3. 4
4. -4
-2
1. -f(x)
2. f(x)
3. f(-x)
4. 2f(x)
2f(x)
1. 10
2. 15
3. 20
4. 25
25