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`1/8``1/32``1/16``1/12`

Answer :

CSolution :

`sin 10^(@)sin 30^(@)sin50^(@) sin 70^(@)` <br> `=sin 10^(@)sin(60^(@)-10^(@))sin(60^(@)+10^(@))sin30^(@)` <br> `=(1)/(4)sin(3xx10^(@))sin30^(@)=(1)/(4)sin^(2)30^(@)=(1)/(16)` Transcript

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00:00 - 00:59 | in this question we have to find the value of sin 10 degree into sin 30 degree into sin 50 degree into sin 70 degree first of all let's write the equation which is given the question that is sunao hit simplify this and simplifying we will get everything sin 10 degrees on one side and we know that sin 30 is 1 by 2 is to 1 by 2 and we will write science 50m sin70 together into sin 70 ok now we will multiply and divide two with the situation and we will get 1 by 4 sin 10 degree this will be to sin50degree into sin 70 degree |

01:00 - 01:59 | Shravan Vinod a formula that is 2 sin a sin b OK I will write the formula here now 2 sin a sin b is equal to cos of a minus b into cos of a plus we write sunao simplifying you will get 1 by 4 sin 10 degree physics formula we will get a mines bi in 50 - 70 and discourse and cause of -20 is it will get cost of 20 degree minus 50 + 7120 and we will get cause of 120 degree |

02:00 - 02:59 | now simplifying we will get signed 10 degree cos 120 degree and we know that cos 120 degrees minus sin 30 degree and Sin 37 by 2 and minus sin 30 + 1 by two right ok I will right here that cos 120 degree is equal to minus of sin 30 degree right now I will multiply 1 by 4 sin 10 with both of these terms and I will get 1 by 4 sin tan cos of 20 degree + 1 by 8 science |

03:00 - 03:59 | right now I will multiply and divide by 2 in system and with this I will get one bite into to sign into cos 20 this as it is right now using the formula that is 2 sin a cos b ok we will use if formula 2 sin a cos b which is equal to sign of a + b + sin of a minus b right now we will apply this form and we will get 1 by 8 2 sin a cos b |

04:00 - 04:59 | sign of a sin a + b sin 10 20 30 we will get sin 30 sin 30 + sign of a minus b it is 10 - 20 is -10 and asali minus sin 10 right and this + 1 by 8 9 10 degree as it is now video 1 b sin 30 12 dissolution by to hazardous and this is signed 10 degree B sin 10 degree disturb I will multiply with both of these terms and I will get one by 16 sin 10 by 8 - of sin |

05:00 - 05:59 | 10 free by 8 is 1 by 8 degree this and this term will get cancelled and I will be left with one by 16 which is show the correct option is option 31 by 60 thank you |

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