Question

Q27. What must be added to 4 - 3x + 9x2 to get 12 + 4x2 – x3?​

Answer 1

Question: What must be added to

$4 - 3 x + 9 {x}^{2} \: to \: get \: \\ 12 + 4 {x}^{2} - {x}^{3}$

Answer : -x³ - 5x² + 3x +8

Let's write it 1st in proper order...

Let the number that is to be added in 4 - 3x + 9x² to get 12 + 4x² - x³ be z

THEREFORE:

OUR EQUATION WILL BE ⬇️

$4 - 3x + 9 {x}^{2} + (z) = 12 + 4 {x}^{2} - {x}^{3}$

$z = 12 + 4 {x}^{2} - {x}^{3} - (4 - 3x + 9 {x}^{2} ) \\ = > 12 + 4 {x}^{2} - {x}^{3} - 4 + 3x - 9 {x}^{2} \\ = > 12 - 4 + 4 {x}^{2} - 9 {x}^{2} - {x}^{3 } + 3x \\ = > 8 - 5 {x}^{2} - {x}^{3} + 3x \\ = > - {x}^{3} - 5 {x}^{2} + 3x + 8 \: answer$

Hope this helps you..

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