C, D are points defined by position vectors c and d. Magnitude of c is 5, mag of d is 7, c dotproduct d is 4 ie c.d = 4, find the magnitude of vector CD.(adsbygoogle = window.adsbygoogle || []).push({});

So i started this way

c.d = magc*magdcos@

= 35cos@, @ = 83.4 degrees

But still no idea how do get magnitude of vector cd. Thank you!

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# Homework Help: Magnitude of vector CD?

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