Question

Reduce the following expression using BODMAS rule: $2y-1(y-y^2)+5y\left[\right(-2y\left)\right(y^2-1\left)\right]$

• A. $10y^4+11y^2+y$
• B. $-10y^4+11y^2-y$
• C. $-10y^4+11y^2+y$
• D. $-10y^4-11y^2+y$

Answer 1

The correct option is C $-10y^4+11y^2+y$

$2y-1(y-y^2)+5y\left[\right(-2y\left)\right(y^2-1\left)\right]$
We need to follow BODMAS rule.
=> Brackets (parts of a calculation inside brackets always come first).
=> Orders (numbers involving powers or square roots).
=> Division.
=> Multiplication.
=> Addition.
=> Subtraction.
$=$ $2y-y+y^2+5y[-2y^3+2y]$
$=$ $y+y^2-10y^4+10y^2$
$=$ $-10y^4+11y^2+y$