Question

If a = -1 , b = 2,then find the value of ab - ba

Answer 1

We know
A=-1&B=2

Then,

ab-ba

-1*2-(2*-1)

-2+2

0

Answer 2

Question

If a = -1 , b = 2,then find the value of ab - ba

$\rule{300}{1}$

Answer

Using the value of 'a' and 'b' given, we must replace 'a' and 'b' with the given value and solve.

So here we need to solve ⇒ ab-ba

So the value of 'a' is -1 and the value of 'b' is 2.

(-1 × 2) - (2 × -1)

-2 - (-2)

-2 + 2

0

∴ ab-ba = 0 when 'a' = -1 and 'b' = -2.

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Additional Information

So now I am going to explain how we can solve expression with given value of variables.

Consider the expression to be ⇒ 3p+2a+k

here let the given values be ⇒

• p = 2
• a = 10
• k = 9

To solve such questions we must substitute the given values and solve. So let's try the example question.

3p+2a+k

(3×2) + (2×10) + (9)

6 + 20 + 9

35

So our final answer would be 35.

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