Find II 2e-3f II^2 assuming that e & f are unit vectors such that II e +f II=sqrt(3/2).
1 answer:
<span>We are given that ||e|| = 1, ||f|| = 1. </span>
<span>Since ||e + f|| = sqrt(3/2), we have </span>
<span>3/2 = (e + f) dot (e + f) </span>
<span>= (e dot e) + 2(e dot f) + (f dot f) </span>
<span>= ||e||^2 + 2(e dot f) + ||f||^2 </span>
<span>= 1^2 + 2(e dot f) + 1^2 </span>
<span>= 2 + 2(e dot f). </span>
<span>So e dot f = -1/4. </span>
<span>Therefore, </span>
<span>||2e - 3f||^2 = (2e - 3f) dot (2e - 3f) </span>
<span>= 4(e dot e) - 12(e dot f) + 9(f dot f) </span>
<span>= 4||e||^2 - 12(e dot f) + 9||f||^2 </span>
<span>= 4(1)^2 - 12(-1/4) + 9(1)^2 </span>
<span>= 4 + 3 + 9 </span>
<span>= 16. </span>
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Answer:
6
Step-by-step explanation:
|-6| = 6
|6| = 6
- -6 = +6
so, we have
6 - 6 + 6 = 6
N= 12 or - 12 I’m not sure I did it in my head
4x^2+6x=12
16x+6x=12
22x=12
x=12/22 or 0.55
The decimal is rounded to the nearest hundreth
From the shown figure we have:
1) FE = FG ⇒⇒⇒ given
2) ∠EFZ = ∠GFZ ⇒⇒⇒ given
3) FZ = FZ ⇒⇒⇒ <span>Reflexive Property
∴ The triangles are </span><span>c<span>ongruent by SAS
The correct choice is: </span></span>
<span>by SAS only</span>