Solution
$$y=2x+1$$
$$2x-y=-1$$.......(1)
Cubing on both sides, we get
$$8x^3-y^3-3.2x.y\left(2x-y\right)=-1$$
$$8x^3-y^3-6xy\left(-1\right)=-1$$ [From (1)]
$$8x^3-y^3+6xy=-1$$
Hence, the correct answer is Option B
Create a FREE account and get:
- Free SSC Study Material - 18000 Questions
- 230+ SSC previous papers with solutions PDF
- 100+ SSC Online Tests for Free
