If a, b are constants then, $V a r (a + b X)$ is

V a r (a) + V a r (X)

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V a r (a) - V a r (X)

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b^{2} V a r (X)

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None of these

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Solution

The correct option is C $b^{2} V a r (X)$
$V a r (a + b X) = V a r (a) + V a r (b X)$

$⟹ V a r (a + b X) = 0 + V a r (b X)$ (Since, $V a r (c) = 0$ )

$⟹ V a r (a + b X) = b^{2} V a r (X)$ (Since, $V a r (a X) = a^{2} V a r (X)$ )

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If a, b are constants then, Var(a+bX) is

The correct option is C b2Var(X)Var(a+bX)=Var(a)+Var(bX)⟹Var(a+bX)=0+Var(bX) (Since, Var(c)=0)⟹Var(a+bX)=b2Var(X) (Since, Var(aX)=a2Var(X))

If a, b are constants then, $V a r (a + b X)$ is

The correct option is C $b^{2} V a r (X)$
$V a r (a + b X) = V a r (a) + V a r (b X)$

$⟹ V a r (a + b X) = 0 + V a r (b X)$ (Since, $V a r (c) = 0$ )

$⟹ V a r (a + b X) = b^{2} V a r (X)$ (Since, $V a r (a X) = a^{2} V a r (X)$ )