F.2 Law of Indices

1.(6^y)=1296
=36^2
=6^4
y=4

2.(5^-x)=125
=5^3
-x=3
x=-3

3.2x(3^y+1)=486
(3^y+1)=243
y+1 =5
y=4

4.)(2^y-1)-3=29
y-1=5
y=6

5. 5/7X(3^2y)=5/189
(3^2y)=3^-3
2y=-3
y= -1.5

6. (2^(2x)) (2^(1-x)) = 1/16
(2^2x+1-x)=2^-4
x+1= -4
x= -5

7. 40 (decimal) =101000(binary)
44(decimal) =101100 (binary)
48(decimal)=110000(binary )

Hope can help u

1.

6^y = 1296
6^y = 6^4
y = 4

2.

5^(-x) = 125
5^(-x) = 5^3
-x = 3
x = -3

3.

2 × (3^(y + 1)) = 486
3^(y + 1) = 243
3^(y + 1) = 3^5
y + 1 = 5
y = 4

4.

(2^(y - 1)) - 3 = 29
2^(y - 1) = 32
2^(y - 1) = 2^5
y - 1 = 5
y = 6

5.

(5/7) × (3^(2y) = 5/189
3^(2y) = 1/27
3^(2y) = 3^(-3)
2y = -3
y = -3/2

6.

(2^(2x)) (2^(1-x)) = 1/16
2^((2x) + (1-x)) = 2^(-4)
x + 1 = -4
x = -5

2012-06-25 10:27:18 補充：
7.

100000_2 = 32_10
100100_2 = 36_10
101000_2 = 40_10
101100_2 = 44_10
110000_2 = 48_10
110100_2 = 52_10
111000_2 = 56_10
111100_2 = 60_10

all the last two digits are 0