giải hộ mình với ạ,,,, Question giải hộ mình với ạ,,,, in progress 0 Môn Toán Jezebel 5 years 2021-05-16T17:22:02+00:00 2021-05-16T17:22:02+00:00 2 Answers 24 views 0
Answers ( )
`a) P(x) + Q(x) = (-5x^4 + 7x^3 -3x^2 -5-2x) + (3x-4x^4 + 6x^3-1)`
` = -5x^4 + 7x^3 -3x^2 -5-2x + 3x-4x^4 + 6x^3-1`
` = (-5x^4 – 4x^4)+(7x^3 + 6x^3) – 3x^2 – (2x-3x) – (5+1)`
` = -9x^4 + 13x^3 -3x^2 + x -6`
`b) P(x) – Q(x) = (-5x^4 + 7x^3 -3x^2 -5-2x) – (3x-4x^4 + 6x^3-1)`
` = -5x^4 + 7x^3 -3x^2 -5-2x – 3x+ 4x^4 – 6x^3+1`
` =(-5x^4 + 4x^4) + (7x^3 – 6x^3) -3x^2 + (-2x-3x) + (-5+1)`
` = -x^4 + x^3 -3x^2 -5x – 4`
\[●\]Đáp án+Giải thích các bước giải:
\[a) P(x) + Q(x) = (-5x^4 + 7x^3 -3x^2 -5-2x) + (3x-4x^4 + 6x^3-1)\\= -5x^4 + 7x^3 -3x^2 -5-2x + 3x-4x^4 + 6x^3-1\\= -9x^4 + 13x^3 -3x^2 + x -6\\b) P(x) – Q(x) = (-5x^4 + 7x^3 -3x^2 -5-2x) – (3x-4x^4 + 6x^3-1)\\= -5x^4 + 7x^3 -3x^2 -5-2x – 3x+ 4x^4 – 6x^3+1\\= -x^4 + x^3 -3x^2 -5x – 4\]