IDNLearn.com is the perfect place to get detailed and accurate answers to your questions. Get prompt and accurate answers to your questions from our community of experts who are always ready to help.

y4+5y2+9 factorise please help me​

Y45y29 Factorise Please Help Me class=

Sagot :

[tex]\displaystyle\ y^4 +5y^2+9=(y^2+3)^2-y^2=(y^2-y+3)(y^2+y+3)[/tex]

Answer:

Solution given;

[tex] y^{4}+5y²+9[/tex]

keeping [tex]y^{4} and 9 together [/tex]

[tex]y^{4}+9+5y²[/tex]

[tex](y²)²+3²+5y²[/tex].....[I]

we have

a²+b²=(a+b)²-2ab

or

a²+b²=(a-b)²+2ab

same like that

[tex](y²)²+3²=(y²+3)²-6y² or (y²-3)²+6y²[/tex]

remember that while adding or subtracting the left term 5y² either adding 6y²or subtracting 6y²

should make the term perfect square

while subtracting it makes perfect square

so

we take

(y²)²+3²=(y²+3)²-6y²

again

substituting value of

(y²)²+3² in equation 1 and it becomes

(y²+3)²-6y²+5y²

solve like terms

(y²+3)²-y²

again

we have

a²-b²=(a+b)(a-b)

by using this.

(y²+3+y)(y²+3-y)

rearrange it

(y²+y+3)(y²-y+3) is a required factorisation form.