Factorisation of algebraic expressions 3

SMP NEGERI 2 SINDANG INDRAMAYU

I.FACTORISATION OF SQUARE FROM

a where a = 1 Suppose that the factors are p and q

So….. = ( x + p ) ( x + q ), p + q = b p. q = c

Examples :

a) ( + p)( + q) P+q = 5, p.q = 6The factors of 6 are : 1, 2, 3, 6….find the factors those are the sum are 5So……..2.3 = 62+3= 5P= 2, q = 3

And then ( + 3 ) + 2 )

b) = ( + p)( – q) p.q = p+q= 5 p = 7, q = 2, so……

= ( + 7)( – 2)

Exercises :

1.Factorise the following expressiona) ))b) ) ))c) ))d) ) ))e) ))F) ))

Next….g) ))h) ))i) ))j) ))k) 24 ))l) 60 ))m) 30 ))

II.FACTORISATION OF SQUARE FROMa where a 1Remember that , where a = 1

So the factors are :( + p )( + q) , a.c = p.q and b = p+q

But if : a where a 1

So….. = (+ + )

= ( + ) ( + )

= (+ + )

Consider that, = b ………. and =

Examples :a) 5

= b ………. and =

( + ) ( + ) = ( + ) ( + )

= ( + ) ( + )= ( + (-2) )(5 + (-2))

=( ,

so , the factors are (

2nd way :a) 5 but have to match to (-12) as the sum 4(5 2) ( = = (-2)() + ()(5) 5

3rd way a) 5

5

5 (,

So the factors are (

ExercisesCobalah selesaikan contoh soal berikut

1. 3

2.

3.

4.

5.

6.

7.

8.

9.

10. 10 + 27x

Remember :

YOU CAN if you THINK YOU CAN

WHERE THERE IS WILL THERE IS A WAY………

Do you agree ……..? Good……….

Buku sumber : Pelajaran MATEMATIKA 3 Untuk SLTP kelas 3

Penulis : Mochammad Nurdin dkkDepartemen Pendidikan dan KebudayaanProyek Pengembangan Buku dan Minat Baca Tahun Anggaran 1998/1999