Use Coupon: CART20 and get 20% off on all online Study Material

Total Price: R

There are no items in this cart.
Continue Shopping
Get instant 20% OFF on Online Material.
coupon code: MOB20 | View Course list

Get extra R 150 off


to prove that

(r=1 to r=7)∑tan2r∏/16=(r=1 to r=7)∑cot2r∏/16=35

7 years ago


Answers : (1)

										Hello Student, Please find the solution

(r=1 to r=7)∑tan2r∏/16
= tan2∏/16 + tan22∏/16+ tan23∏/16+ tan24∏/16+ tan25∏/16+ tan26∏/16+ tan27∏/16
rearranging terms
=tan2∏/16+ tan27∏/16+ tan22∏/16+ tan26∏/16+ tan23∏/16tan25∏/16+ tan24∏/16
[Now, tan24∏/16 = tan2∏/4 = 1]

tan2∏/16+ tan27∏/16
= tan2∏/16+ cot2∏/16
=now you can convert to sine, cosine and find the ans

All the best

2 years ago

Post Your Answer

Other Related Questions on Trigonometry

sin^2A-sin^2B=(sinA+B)(sinA-B)how can it be true?? It should be (sinA-sinB)(sinA+sinB).please help!!
Hi Riya You can use the formula for Sum and Difference for Sin to get the required solution. Have look below and hope you understand the derivation
Ajay 3 months ago
Thank you .I got it now. I was not equating the second last LHS to sin2x but now I got it thanks a lot .I need to concentrate more.
riya 3 months ago
let a,b,c be the sides oppositwe the angles A,B,C of triangle ABC.find the value of k a+b=ck
refer R.D. sharma Book there you will find all the answers of your queries. its the best book for all the geometric questions
aadish jain one month ago
If the line joining circumcentr and incentre is parallel to BC then cosB+cosC= I had seen that above image submitted by me is unclear . so to view the solution please click the below link . I don’t see ny option to attach image. copy ...
2017 years ago
Drop perpendiculars from I and O on to BC and let the feet of the perpendiculars be P and Q resp. IP = in-radius = r. Also OQ = R cos A. Since OI is parallel to BC, we have IP = OQ i.e. r = ...
4 days ago
show that the tangent to y^2= 4ax at (a,-2a) touches the parabola x^2= 4ay.
Differntiate y^2= 4ax, 2y.dy/dx = 4a dy/dx = 2a/y dy/dx = 2a/-2a = -1 Thus for x^2 = 4ay the slope should also come to -1 as they both have a common tangent. Now doing, 2x = 4ady/dx2 dy/dx2 ...
Vikas TU 2 months ago
what is meant by vector triple product?????????????????????????????
If the scalar triple point is equal to zero, then the three vectors a, b, and c are coplanar. multiplication of three vectors also called the vector three product.
mohan 7 months ago
If the scalar triple product is equal to zero, then the three vectors a, b, and c are coplanar, since the "parallelepiped" defined by them would be flat and have no volum
Prabhakar ch 7 months ago
multiplication of three vectors iscalled as vector 3product. this is very important in vectors and also it is very useful.
RIYAZSHAIK 7 months ago
Please tell if you know any short tricks of mathematics for jee
Dear Students, Maths needs alot of practise and thus please solve more number of questions. Tricks are of course there in every topics. You can get those tricks from the study material...
Vijay Mukati 11 months ago
Dear Harshil Chauhan, For mathematics there is no shortcuts except someone,the only thing is you can practise much number of problems.
SAI SARDAR 10 months ago
Every day chapter complete that day and practice at least 3 hours.Read NCERT books properly these are some trics for matha.
NARAYANA 10 months ago
View all Questions »

  • Complete JEE Main/Advanced Course and Test Series
  • OFFERED PRICE: R 15,000
  • View Details
Get extra R 3,750 off

Get extra R 150 off

More Questions On Trigonometry

Ask Experts

Have any Question? Ask Experts

Post Question

Answer ‘n’ Earn
Attractive Gift
To Win!!!
Click Here for details