有關於幾條唔識既F.1 數題!!

1. Find a two-digit number that satisfiesthe following conditions:
(a)The tens-digit is greater that the unit-digit by 2.
e.g. [64] : 6-4=2
(b)The square of the unit-digit is large than twice the tens-digit.
e.g.[64]:6+6<4x4
A possible solution is 64. Would you suggest other solutions?
Satisfy (a) = 97, 86, 75,64, 53, 42, 31
Satisfy (b) = 97, 86, 75
2.What can be multiplied to X-2 to give aproduct containing the term
-3X2? Find the polynomial.[Note: There are more than one answer.]
∵-3X2=X(-3X) or (-2)(3X2/2)
∴the polynomial is (-3X) or (3X2/2)
3.Peter has a wire which is 30cm long. Hewants to bend
it into a shape such that it encloses a maximum area.
Would you help Peter to find the ideal shape he want?
The square.
The largest area of any rectangle with a given perimeter willoccur when a square is formed.
4.Write the algebraic expression 5/3 x- 2 in2 different word sentences.
1) Subtract 2 from the product of 5 and x/3.
2) 2 less than the quotient 5x divided by 3.

5. The first term and the fifth term of a sequenceare 1 and 16
respectively. Find the second, the third and the fourth terms
of the sequence.
T(1)=1=20=2(1-1)
T(5)=16=24=2(5-1)
T(n)=2(n-1)
T(2)=21=2,T(3)=22=4, T(4)=23=8
6.Find a function such that when the input x is -3. the output y is 1/2
y=x/-6;
y=x+7/2;
y=7/2+x;
y=2x-11/2
..so on
7.Find two possible 3-digit denary numbers such that each of them
can be converted into a 8 - digit binary number and a 2 - digit
hexadecimal number.
The max. value = 25610=111111112=FF16
: : :
The min. value = 12810=100000002=8016
8.Find two possible binary numbers which are divisible by both
6 and 8 when they are converted into denary numbers.
(any multiples of 24)
2410=110002
4810=1100002
7210=10010002
9610=11000002
..so on..