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Prove that 4cos(2pi)/7dotcospi/7-1=2cos(...

Prove that `4cos(2pi)/7dotcospi/7-1=2cos(2pi)/7dot`

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Prove that 4cos((2pi)/7).cos(pi/7)-1=2cos((2pi)/7) .

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Prove that: cos(pi/7)cos((2pi)/7)cos((4pi)/7)=-1/8

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3.Prove that (i) "cos((2pi)/7)*cos((4pi)/7)*cos((8pi)/7)=1/8

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Prove that cos(2pi)/(15)cos(4pi)/(15)cos(8pi)/(15)cos(14pi)/(15)=1/(16)

Prove that cos((2pi)/(15))cos((4pi)/(15))cos((8pi)/(15))cos((14pi)/(15))=1/(16)

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CENGAGE ENGLISH-TRIGONOMETRIC FUNCTIONS-All Questions
  1. Show that sin^2 5^0+sin^2 10^0+sin^2 15^0++sin^2 90^0=9 1/2dot

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  2. Solve (sin^3x/2-cos^3x/2)/(2+sinx)=(cosx)/3

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  3. Prove that 4cos(2pi)/7dotcospi/7-1=2cos(2pi)/7dot

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  4. Suppose alpha,beta,gammaa n ddelta are the interior angles of regular ...

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  5. Find the value of cos^2pi/(16)+cos^2(3pi)/(16)+cos^2(5pi)/(16)+cos^2(7...

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  6. Solve (sqrt(5)-1)/(sinx)+(sqrt(10+2sqrt(5)))/(cosx)=8,x in (0,pi/2)

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  7. Prove that cos(2pi)/(15)cos(4pi)/(15)cos(8pi)/(15)cos(14pi)/(15)=1/(16...

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  8. Let L be the line of intersection of the planes 2x""+""3y""+""z""=""...

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  9. If sin(120° – α) = sin(120° – β) and 0 < α, β < π then find the relati...

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  10. Solve cosxcos2xcos3x=1/4

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  11. Prove that: sin6^(@)sin42^(@)sin66^(@)sin78^(@)=1/16

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  12. Find the sign of the values of tan113^0-cos107^0=a and tan107^0-cos105...

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  13. Solve the equation (sqrt(3))/2sinx-cosx=cos^2x

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  14. Each equation contains statements given in two columns which have to b...

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  15. If xsina+ysin2a+zsin3a=sin4a xsinb+ysin2b+zsin3b=sin4b, xsinc+ysin2c...

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  16. Prove that (sin-cosx+1)/(sinx+cosx-1)=secx+tanx

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  17. The lengths of the medians through acute angles of a right-angled tr...

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  18. If 2tan^2x-5secx=1 is satisfied by exactly seven distinct values of x ...

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  19. In triangle A B C ,tanA+tanB+tanC=6a n dtanAtanB=2, then the values o...

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  20. If 2cosx+sinx=1, then find the value of 7cosx+6sinxdot

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