Question

if x=1/2-√3 find the value of x^3 -2x^2 -7x +5​

Answer 1

Answer:

Step-by-step explanation:

X=1/(2-√3)

Orx=(2+√3)/2²-(√3)²

Or, x=2+√3

Or x-2=√3

Or(x-2)²=(√3)². (squaring both sides)

Or,x²-4x+4=3

Or,x²-4x+1=0

Now ( x³-2x²-7x+5)÷(x²-4x+1)=(x+2)(quotient) and 3(remainder)

We know that

Dividend=(divisor×quotient)+remainder

So x³-2x²-7x+5=(x²-4x+1)(x+2)+3

=0×(x+2)+3

=0+3

=3

Thus x³+2x²-7x+5=3 (answer)

Thank you