Question

Gi ải giúp mình vs ah

Answer 1

a: \(M\left(x\right)=3x^2+x^2+4x^4-x-3x^3+5x^4+x^2-6\)

\(=\left(4x^4+5x^4\right)-3x^3+\left(3x^2+x^2+x^2\right)-x-6\)

\(=9x^4-3x^3+5x^2-x-6\)

\(N\left(x\right)=-x^2-x^4+4x^3-x^2-5x^3+3x+1+x\)

\(=-x^4+\left(4x^3-5x^3\right)+\left(-x^2-x^2\right)+4x+1\)

\(=-x^4-x^3-2x^2+4x+1\)

b: M(x)+N(x)

\(=9x^4-3x^3+5x^2-x-6-x^4-x^3-2x^2+4x+1\)

\(=8x^4-4x^3+3x^2+3x-5\)

M(x)-N(x)

\(=9x^4-3x^3+5x^2-x-6+x^4+x^3+2x^2-4x-1\)

\(=10x^4-2x^3+7x^2-5x-7\)

c: P(x)=M(x)-N(x)

\(=10x^4-2x^3+7x^2-5x-7\)

bậc là 4

hệ số cao nhất là 10

Hệ số tự do là -7

d: \(P\left(-2\right)=10\cdot\left(-2\right)^4-2\cdot\left(-2\right)^3+7\cdot\left(-2\right)^2-5\cdot\left(-2\right)-7\)

\(=10\cdot16+2\cdot8+7\cdot4+10-7\)

=160+16+28+3

=176+31

=207