Maths-Identity(F.2)

1. If x² - 3x + 4 ≡ Ax² + Bx - 3x + 2C, FIND a,b and c


x² - 3x + 4 ≡ Ax² + Bx - 3x + 2c
x² - 3x + 4 ≡ Ax² + (B - 3)x + 2c

Compare the x² terms on the both sides:
A = 1

Compare the constant terms on the both sides:
2C = 4
C = 2

Compare the x terms on the both sides:
B - 3 = -3
B = 0

Hence, A = 1, B = 0, C = 2

It's conceptually wrong to do term deletion over identity. Identity is not the same as equation. You can only do comparison over the same terms on both sides.

1. If x^2-3x+4=Ax^2+Bx-3x+2c,FIND a,b and c
x^2+4=Ax^2+Bx+2c (First delete the same things (-3x))
Ax^2=x^2
A=1
4=Bx+2c (First delete the same things (Ax^2))
c=2
B=0
A=1, B=0, C=2