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DominiRican1013
 one year ago
If cos(x)cos(pi/7)+sin(x)sin(pi/7)=V2/2
DominiRican1013
 one year ago
If cos(x)cos(pi/7)+sin(x)sin(pi/7)=V2/2

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.01. ∫ cos³(πx) dx 2. ∫ cos²(πx) cos(πx) dx 3. ∫(1  sin²(πx)) cos(πx) dx 4. ∫ cos(πx) dx  ∫ sin²(πx) cos(πx) dx Set u=πx, du=π dx Set v=sin(u), dv=cos(u) du 5. 1 ⁄ π ∫ cos(u) du  1 ⁄ π ∫ v² dv 6. 1 ⁄ π [ ∫ cos(u) du  ∫ v² dv ] 7. 1 ⁄ π [ sin(u)  v³ ⁄ 3 ] + C 8. 1 ⁄ π [ sin(πx)  sin³(πx) ⁄ 3 ] + C 9. sin(πx) ⁄ π  sin³(πx) ⁄ (3π) + C One day you will know Euler's as the most versatile tidbit of knowledge on the planet. 10. ∫ cos³(πx) dx 11. ∫ [(e^(iπx) + e^(iπx)) ⁄ 2]³ dx 12. ⅛ ∫ [e^(iπx) + e^(iπx)]³ dx 13. ⅛ ∫ [e^(3iπx) + e^(3iπx) + 3e^(iπx) + 3e^(iπx)] dx 14. ⅛ [∫ e^(3iπx) dx + ∫ e^(3iπx) dx + 3∫ e^(iπx) dx + 3∫ e^(iπx) dx] 15. ⅛ [e^(3iπx) ⁄ (3iπ) + e^(3iπx) ⁄ (3iπ) + 3e^(iπx) ⁄ (iπ) + 3e^(iπx) ⁄ (iπ)] + C 16. ⅛ [(1 ⁄ (3iπ))(e^(3iπx)  e^(3iπx)) + (3 ⁄ (iπ))(e^(iπx)  e^(iπx))] + C 17. ⅛ [(1 ⁄ (3iπ))(2i sin(3πx)) + (3 ⁄ (iπ))(2i sin(πx))] + C 18. ⅛ [(2 sin(3πx)) ⁄ (3π) + (6 sin(πx)) ⁄ π] + C 19. [sin(3πx) + 9 sin(πx)] ⁄ (12π) + C Which is another way of saying the same thing. Pick your poison. But note the link below. Wolfram's alpha sets it up with Euler's.

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0If \[\cos(x)\cos(\frac{ \pi }{ 7 })+\sin(x)\sin(\frac{ \pi }{ 7 })={\frac{ \sqrt{2} }{ 2 }}\] then x can equal:(check all that apply)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0LHS = cos (x  pi/7)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0cos (x  pi/7) = sqrt2/2

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0Woud you like me to put the choices?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0ang;es whose cosine is sqrt2/2 = 3pi/4 and 5pi/4 ( in the range 0 to 2pi)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0x  pi7 = 3pi/4 and x  pi/7 = 5pi/4 solve for x

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0\[A. 7\pi/4+\pi/7+2npi\]

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0\[B. 5\pi/4+\pi/7+2npi\]

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0\[C. \pi/4+\pi/7+2npi\]

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0\[D. 3\pi/4+\pi/7+2npi\]

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0the 2n pi means that the solutions contain an infinite number of higher angles  you should be able to find the correct options from my last post

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0x  pi7 = 3pi/4 add pi/7 to both sides x = 3pi/4 + pi/7

LynFran
 one year ago
Best ResponseYou've already chosen the best response.2the cos function dw:1437060458196:dw

LynFran
 one year ago
Best ResponseYou've already chosen the best response.2what is your principal value here?

LynFran
 one year ago
Best ResponseYou've already chosen the best response.2no..dw:1437060724407:dw

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0I've done one of them for you in my last post

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0I got that one.... do any of the others apply because the problem asks for check all that apply

LynFran
 one year ago
Best ResponseYou've already chosen the best response.2so what the other option ?

DominiRican1013
 one year ago
Best ResponseYou've already chosen the best response.0it was B and D not C :)
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