What is the general solution for cos(A)=-4/5 ?

The general solution for cos(A)=-4/5 is A=2.49809…+2pin,A=-2.49809…+2pin

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

cos(A)=-4/5

cos (A) = - \frac{4}{5}

A = 2.49809 \dots + 2 πn, A = - 2.49809 \dots + 2 πn

Solution steps

cos (A) = - \frac{4}{5}

Apply trig inverse properties

A = arccos (- \frac{4}{5}) + 2 πn, A = - arccos (- \frac{4}{5}) + 2 πn

Show solutions in decimal form

A = 2.49809 \dots + 2 πn, A = - 2.49809 \dots + 2 πn

4 cot^{2} (x) = cos^{2} (x) + sin^{2} (x) - 1

sin (3 x) cos (x) - cos (3 x) sin (x) = 0

4 sin (2 x) = - 2

x, sin^{2} (x) = 0

cos (t) = - \frac{3}{4}

What is the general solution for cos(A)=-4/5 ?
The general solution for cos(A)=-4/5 is A=2.49809…+2pin,A=-2.49809…+2pin