Question

Which equations are true? Select all that apply. Options:

Answer 1

Answer: The correct options are,

Square root of -4 = 2i

Square root of -49 = 7i

Step-by-step explanation:

∵ $\sqrt{-4}=\sqrt{4(-1)} = \sqrt{4i^2}= \sqrt{(2i)^2}= 2i$

( Since, i² = - 1 )

Similarly,

$\sqrt{-49}=\sqrt{49(-1)} = \sqrt{49i^2}= \sqrt{(7i)^2}= 7i$

$\sqrt{-25}=\sqrt{25(-1)} = \sqrt{25i^2}= \sqrt{(5i)^2}= 5i$

Also,

$-\sqrt{36}=-\sqrt{6^2}=-6$

$-\sqrt{81}=-\sqrt{9^2} = -9$

$-\sqrt{100}=-\sqrt{10^2}=-10$

Answer 2

1;2;5 are the correct statements