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`sin36^(@),sin18^(@)``sin18^(@),cos36^(@)``sin36^(@),cos18^(@)``cos 18^(@),cos36^(@)`

Answer :

BSolution :

`4x^(2)-2sqrt(5)x+1=0` <br> `therefore x=(2sqrt(5)+-2)/(8)=(sqrt(5)+-1)/(4)` <br> `therefore` Roots are `sin 18^(@)` and `cos36^(@)` Transcript

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00:00 - 00:59 | the roots of the quadratic equation 4x square minus 2 root 5 x + 1 is equal to zero Hour sin36 sin 18 sin 18 cos 36 sin 36 ko setting ko settings cos36 so let's take our equation quadratic equation we have 4 x square minus 2 root 5 x + 1 is equal to zero values are formula for quadratic for calculating the roots of the equation that is X is equal to minus b + - root b square - 4ac upon to where where are b is minus 2 root 5 is 4 and C |

01:00 - 01:59 | is one so from here if we put our values in the formula will get x is equal to minus b minus of be that is minus 2 root 5 + - root b square is minus 2 root 5 x square - 4 into 4 into one that is a and c upon you have to wear a formula is account to a to in 24 so x is equal to 2 minus minus cancel 2 root 5 plus minus 2 root 5 whole square is 2 into 244925 is 20 |

02:00 - 02:59 | - 4 into 4 16 into one upon two way that is it so x is equal to 2 root 5 + minus root 4.8 that is X is equal to 2 root 5 + 2 by 8 and 2 root 5 minus 2.8 so if we take out two common we get root 5 + 1 by 4 and root 5 minus 1 by 4 we know that this is our X we know that the values of |

03:00 - 03:59 | values of sin 18 degree is root 5 minus 1 by 4 and Cos 36 degree is root 5 + 1 by 4 that is answer is sin 18 degree and Cos 36 degree values of sin 80 this is the value of sin square 36 degree and this is the value of sin 18 degree so he we have our answer sin 18 sin 18 and Cos 36 that is option number to thank you |

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