Prove it equivalent

Help me please provet it 1,2,3,and 4 are equivalent

#Algebra

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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

What have you done? What have you tried? Where are you stuck?

Calvin Lin Staff - 4 years, 8 months ago

From point 4 to point 1 i stucked no idea

Ahmad Nugroho - 4 years, 8 months ago

How do you show that a set is an orthonormal basis? What are the necessary and sufficient conditions?

Calvin Lin Staff - 4 years, 8 months ago

@Calvin Lin – If we have an orthornormal set like the picture , the condition for orthonormal basis are <ui,uj> = 0 , u~=j <ui,uj> = 1 , u=j

<,> is an inner product Sorry i replied by phone

Ahmad Nugroho - 4 years, 8 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$