Your proof is correct and very well done
Using the dot product:
For any vector x, we have
||x|| = √(x • x)
This means that
||w|| = √(w • w)
… = √((u + z) • (u + z))
… = √((u • u) + (u • z) + (z • u) + (z • z))
… = √(||u||² + 2 (u • z) + ||z||²)
We have
u = ⟨2, 12⟩ ⇒ ||u|| = √(2² + 12²) = 2√37
z = ⟨-7, 5⟩ ⇒ ||z|| = √((-7)² + 5²) = √74
u • z = ⟨2, 12⟩ • ⟨-7, 5⟩ = -14 + 60 = 46
and so
||w|| = √((2√37)² + 2•46 + (√74)²)
… = √(4•37 + 2•46 + 74)
… = √314 ≈ 17.720
Alternatively, without mentioning the dot product,
w = u + z = ⟨2, 12⟩ + ⟨-7, 5⟩ = ⟨-5, 17⟩
and so
||w|| = √((-5)² + 17²) = √314 ≈ 17.720
The answer is a translation of 3 units to the left. Can you please (or someone else) please help me with this question that i'm about to ask
Is this sentence correct: " I expected her to apologize, but I'd miscalculated" ? Does that makes sence? if not right please correct that sentence I'LL APRECIATE IT, THANK YOU SO MUCH!
18 glasses of water
3.6/.2=18
Using the points (0,14) and (10,0), the gradient of the line is (14-0)/(0-5) which simplifies to -7/5.
From these points, we can also see that when the x value is zero, the y value is 14. Therefore the y-intercept is 14.
We can then put this into the equation of a straight line, y=mx+c:
y = (-7/5)x + 14
