# If dimensions of A and B are different, then which of the following operation is valid   Option 1) A/B Option 2) $e^-{\frac{A}{B}}$ Option 3) A-B Option 4) A+B

As we learnt in

Error in division x = a/b -

$\dpi{100} \frac{\Delta x}{x}=\pm \left ( \frac{\Delta a}{a}+\frac{\Delta b}{b} \right )$

( maximum fractional error in  $\dpi{100} x$)

- wherein

$\dpi{100} \Delta a$= absolute error in measurement of a

$\dpi{100} \Delta b$= absolute error in measurement of b

$\dpi{100} \Delta x$= absolute error in measurement of x

Quantities having different dimensions can only be divided or multiplied but they cannot be added or subtracted.

Option 1)

A/B

Option is correct

Option 2)

$e^-{\frac{A}{B}}$

Option is incorrect

Option 3)

A-B

Option is incorrect

Option 4)

A+B

Option is incorrect

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