English

Evaluate the Following: tan260∘+4cos245∘+3sec230∘+5cos290cosec30∘+sec60∘-cot230∘ - Mathematics

Advertisements
Advertisements

Question

Evaluate the Following:

`(tan^2 60^@ + 4 cos^2 45^@ + 3 sec^2 30^@ + 5 cos^2 90)/(cosec 30^@ + sec 60^@ - cot^2 30^@)`

Sum
Advertisements

Solution

`(tan^2 60^@ + 4 cos^2 45^@ + 3 sec^2 30^@ + 5 cos^2 90)/(cosec 30^@ + sec 60^@ - cot^2 30^@)`   ...(i)

By trigonometric ratios we have

`tan 60^@ = sqrt3     cos 45^@ = 1/sqrt2    sec 30^@ = 2/sqrt3`

`cos 90^@ = 0      cosec  30^@ = 2      sec 60^@ = 2    cot 30^@ = sqrt3`

By substituting above values in (i), we get

`((sqrt3)^2 + 4.(1/sqrt2)^2 + 2 + [2/sqrt3]^2 + 5(0)^2)/(2 + 2sqrt2 (+ sqrt3)^2)`

= `(3 + 4. 1/2 + 3 4/3)/(4 - 3)` 

= `(3 + 2 + 4)/1`

= 9

shaalaa.com
  Is there an error in this question or solution?
Chapter 10: Trigonometric Ratios - Exercise 10.2 [Page 42]

APPEARS IN

RD Sharma Mathematics [English] Class 10
Chapter 10 Trigonometric Ratios
Exercise 10.2 | Q 17 | Page 42

Video TutorialsVIEW ALL [2]

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×