Question

(z²+ 5)(z²- 6) please help me.please tell fast.please
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Answer 1

$= > {z}^{2} + 5 \times {z}^{2} - 6$

IT IS OF THE FORM (x+a)(x+b)=x^2+(a+b)x+ab

Here x=z^2 , a=5 , b= -6

$= > { {z}^{2} }^{2} + 5 - 6\times{z}^{2} + 5 \times - 6$

$= > {z}^{4} - {z}^{2} - 30$

Answer 2

Answer:

= z^2 +5×z^2 −6

IT IS OF THE FORM (x+a)(x+b)=x^2+(a+b)x+ab

Here x=z^2 , a=5 , b= -6

= { (z)^(2) }^{2} + 5 - 6\times(z)^(2) + 5 \times - 6=>z^2

=2+5−6×z^2+5×−6

= > (z)^(4) - (z)^(2)- 30

=z^4 −z^2 −30