find the value of : tan 45 ° cos e c 30 ° + sec 60 ° c o 45 ° – 5 sin 90 ° 2 cos 0 ° - Mathematics

Question

find the value of :

$\frac{\tan 45 °}{\cos e c 30 °} + \frac{\sec 60 °}{c o 45 °} - \frac{5 \sin 90 °}{2 \cos 0 °}$

Sum

Solution

$\frac{\tan 45 °}{\cos e c 30 °} + \frac{\sec 60 °}{c o 45 °} - \frac{5 \sin 90 °}{2 \cos 0 °} = \frac{1}{2} + \frac{2}{1} + \frac{5}{2}$

$= \frac{1 + 4 - 5}{2} = 0$

shaalaa.com

Trigonometric Ratios of Some Special Angles

Is there an error in this question or solution?

Q 2.2 Q 2.1 Q 2.3

Chapter 23: Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios] - Exercise 23 (A) [Page 291]

APPEARS IN

Selina Concise Mathematics [English] Class 9 ICSE

Chapter 23 Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios]
Exercise 23 (A) | Q 2.2 | Page 291

RELATED QUESTIONS

If x = 30°, verify that

(i) $\tan 2 x = \frac{2 \tan x}{1 - \tan^{2} x}$

(ii) $\sin x = \sqrt{\frac{1 - \cos 2 x}{2}}$

Evaluate cos 48° − sin 42°

Evaluate the following :

$\frac{{\tan 10}^{\circ}}{{\cot 80}^{\circ}}$

Evaluate the following :

$\frac{{\tan 35}^{\circ}}{{\cot 55}^{\circ}} + \frac{{\cot 78}^{\circ}}{{\tan 12}^{\circ}} - 1$

Evaluate the following :

(sin 72° + cos 18°) (sin 72° − cos 18°)

Evaluate the following :

sin 35° sin 55° − cos 35° cos 55°

Express each one of the following in terms of trigonometric ratios of angles lying between 0° and 45°

tan 65° + cot 49°

Prove that $\frac{{\sin 70}^{\circ}}{{\cos 20}^{\circ}} + \frac{\cos e c 20^{\circ}}{{\sec 70}^{\circ}} - 2 {\cos 20}^{\circ} \cos e c 20^{\circ} = 0$

Prove the following :

$\frac{\cos (90 ° - A) \sin (90 ° - A)}{\tan (90 ° - A)} - \sin^{2} A = 0$

Evaluate tan 35° tan 40° tan 50° tan 55°

Evaluate: $\frac{{\sin 18}^{\circ}}{{\cos 72}^{\circ}} + \sqrt{3} [\tan 10 ° \tan 30 ° \tan 40 ° \tan 50 ° \tan 80 °]$

Evaluate: $\frac{{\cos 58}^{\circ}}{{\sin 32}^{\circ}} + \frac{{\sin 22}^{\circ}}{{\cos 68}^{\circ}} - \frac{{\cos 38}^{\circ} \cos e c 52^{\circ}}{{\tan 18}^{\circ} {\tan 35}^{\circ} {\tan 60}^{\circ} {\tan 72}^{\circ} {\tan 65}^{\circ}}$

Prove that:

sin 60° cos 30° + cos 60° . sin 30° = 1

prove that:

sin (2 × 30°) = $\frac{2 \tan 30 °}{1 + \tan^{2} 30 °}$

If $\sqrt{3}$ = 1.732, find (correct to two decimal place) the value of sin 60^o

Given A = 60° and B = 30°,
prove that : sin (A + B) = sin A cos B + cos A sin B

find the value of :

3sin² 30° + 2tan² 60° - 5cos² 45°

Prove that:

cos² 30° - sin² 30° = cos 60°

prove that:

cos (2 x 30°) = $\frac{1 - \tan^{2} 30 °}{1 + \tan^{2} 30 °}$

ABC is an isosceles right-angled triangle. Assuming of AB = BC = x, find the value of each of the following trigonometric ratios: tan 45°

secθ . Cot θ= cosecθ ; write true or false

If $\sqrt{3}$ = 1.732, find (correct to two decimal place) the value of $\frac{2}{\tan 30 °}$

If A =30^o, then prove that :
sin 3A = 3 sin A - 4 sin³A.

If A = 30°;
show that:
$\frac{1 - \cos 2 A}{\sin 2 A} = \tan A$

Without using tables, evaluate the following sec45° sin45° - sin30° sec60°.

Prove that : cos60° . cos30° - sin60° . sin30° = 0

Find the value of 8 sin 2x, cos 4x, sin 6x, when x = 15°

If sin 30° = x and cos 60° = y, then x² + y² is

Evaluate: $\frac{5 \cos^{2} 60 ° + 4 \sec^{2} 30 ° - \tan^{2} 45 °}{\sin^{2} 30 ° + \sin^{2} 60 °}$

find the value of : tan 45 ° cos e c 30 ° + sec 60 ° c o 45 ° – 5 sin 90 ° 2 cos 0 ° - Mathematics

Advertisements

Advertisements

Question

Solution

APPEARS IN

RELATED QUESTIONS

Select a course

find the value of : tan 45 ° cos e c 30 ° + sec 60 ° c o 45 ° – 5 sin 90 ° 2 cos 0 ° - Mathematics

Advertisements

Advertisements

Question

SolutionShow Solution

APPEARS IN

RELATED QUESTIONS

Select a course

Solution