Monday 19 September 2016

MAKING SUBJECT-1




If A = HQR make R the subject of the formula.

Solution

A = HQR

A   =   HQR
HQ      HQ

A   =   R
HQ     

Hence   R =      A 
                      HQ     

TRY THIS………………………..


If K = HDG make G the subject of the formula.

LOGARITHMS 1



Evaluate Log2(2048 x 16).

Solution

= Log2(2048 x 16)

= Log22048 +  Log216          (applying the product rule)

= Log2211 +  Log224             (2048= 211 and 16=24 )

= 11Log22 +  4Log22       ( remember  Logaac = cLogaa )

= (11 x 1) +  (4 x 1)          ( remember  Logaa = 1 )

= 11 + 4

= 15

hence Log2(2048 x 16) = 15

TRY THIS………………


Evaluate Log2(32 x 256). 

FACTORIZATION 1



Factorize 2x2 - x - 15

Solution

= 2x2 - x – 15.  We split the middle term (-x) to be (-6x + 5x).

= 2x2 - 6x + 5x – 15                (-x) = -6x + 5x.

= (2x2 -6x) + (5x - 15)

= 2x(x - 3) + 5(x - 3)

= (2x + 5) (x -3)

Hence 2x2 - x – 20 = (2x + 5) (x - 4) answer.

TRY THIS…..


Factorize 3x2 - 8x – 35.

MID POINT - 1




Find the midpoint of a line from (19, 4) to (5, 10)

Solution

x1=19, x2=5, y1=4, y2=10.

Mid point = (x1 + x2, y1 + y2)
                         2             2

Mid point = (19 + 5,  4 + 10)
                        2          2

Mid point = (24, 14)
                     2    2

Hence midpoint = (12, 7)

TRY THIS……………………..


Find the midpoint of a line from (18, -8) to (-6, 12)