What is det[x + 2, x - 1; x + 1, x]?

Determinants, Adjoint & Inverse · Question 4 of 87

Question 4

EasyOriginal question

What is $\begin{vmatrix} x + 2 & x - 1 \\ x + 1 & x \end{vmatrix}$ ?

2 x - 1

Correct answerYour answer

2 x^{2} + 2 x - 1

Correct answerYour answer

2 x + 1

Correct answerYour answer

1

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

Worth noting

$2x - 1$ subtracts $x^2 - 1$ without the brackets, so its $-1$ keeps the wrong sign.

Ten questions from Determinants, Adjoint & Inverse, at your own pace.

Ten questions from Determinants, Adjoint & Inverse, at your own pace.