English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular Trigonometria >

cos^2(x)<(sqrt(2))/2+sin^2(x)

Solução

cos^{2} (x) < \frac{2}{2} + sin^{2} (x)

Solução

\frac{π}{8} + πn < x < \frac{7 π}{8} + πn

Notação de intervalo

(\frac{π}{8} + πn, \frac{7 π}{8} + πn)

Decimal

0.39269 \dots + πn < x < 2.74889 \dots + πn

Passos da solução

cos^{2} (x) < \frac{2}{2} + sin^{2} (x)

Mova

sin^{2} (x)

para o lado esquerdo

cos^{2} (x) < \frac{2}{2} + sin^{2} (x)

Subtrair

sin^{2} (x)

de ambos os lados

cos^{2} (x) - sin^{2} (x) < \frac{2}{2} + sin^{2} (x) - sin^{2} (x)

cos^{2} (x) - sin^{2} (x) < \frac{2}{2}

cos^{2} (x) - sin^{2} (x) < \frac{2}{2}

Usar a seguinte identidade:

cos^{2} (x) - sin^{2} (x) = cos (2 x)

cos (2 x) < \frac{2}{2}

Para

cos (x) < a

, se

- 1 < a \leq 1

então

arccos (a) + 2 πn < x < 2 π - arccos (a) + 2 πn

arccos (\frac{2}{2}) + 2 πn < 2 x < 2 π - arccos (\frac{2}{2}) + 2 πn

a < u < b

então

a < u and u < b

arccos (\frac{2}{2}) + 2 πn < 2 x and 2 x < 2 π - arccos (\frac{2}{2}) + 2 πn

arccos (\frac{2}{2}) + 2 πn < 2 x : x > \frac{π}{8} + πn

arccos (\frac{2}{2}) + 2 πn < 2 x

Trocar lados

2 x > arccos (\frac{2}{2}) + 2 πn

Simplificar

arccos (\frac{2}{2}) + 2 πn : \frac{π}{4} + 2 πn

arccos (\frac{2}{2}) + 2 πn

Utilizar a seguinte identidade trivial:

arccos (\frac{2}{2}) = \frac{π}{4}

x - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2} 0 \frac{1}{2} \frac{2}{2} \frac{3}{2} 1 arccos (x) π \frac{5 π}{6} \frac{3 π}{4} \frac{2 π}{3} \frac{π}{2} \frac{π}{3} \frac{π}{4} \frac{π}{6} 0 arccos (x) 18 0^{\circ} 15 0^{\circ} 13 5^{\circ} 12 0^{\circ} 9 0^{\circ} 6 0^{\circ} 4 5^{\circ} 3 0^{\circ} 0^{\circ}

= \frac{π}{4} + 2 πn

2 x > \frac{π}{4} + 2 πn

Dividir ambos os lados por

2

2 x > \frac{π}{4} + 2 πn

Dividir ambos os lados por

2

\frac{2 x}{2} > \frac{\frac{π}{4}}{2} + \frac{2 πn}{2}

Simplificar

\frac{2 x}{2} > \frac{\frac{π}{4}}{2} + \frac{2 πn}{2}

Simplificar

\frac{2 x}{2} : x

\frac{2 x}{2}

Dividir:

\frac{2}{2} = 1

= x

Simplificar

\frac{\frac{π}{4}}{2} + \frac{2 πn}{2} : \frac{π}{8} + πn

\frac{\frac{π}{4}}{2} + \frac{2 πn}{2}

\frac{\frac{π}{4}}{2} = \frac{π}{8}

\frac{\frac{π}{4}}{2}

Aplicar as propriedades das frações:

\frac{\frac{b}{c}}{a} = \frac{b}{c \cdot a}

= \frac{π}{4 \cdot 2}

Multiplicar os números:

4 \cdot 2 = 8

= \frac{π}{8}

\frac{2 πn}{2} = πn

\frac{2 πn}{2}

Dividir:

\frac{2}{2} = 1

= πn

= \frac{π}{8} + πn

x > \frac{π}{8} + πn

x > \frac{π}{8} + πn

x > \frac{π}{8} + πn

2 x < 2 π - arccos (\frac{2}{2}) + 2 πn : x < \frac{7 π}{8} + πn

2 x < 2 π - arccos (\frac{2}{2}) + 2 πn

Simplificar

2 π - arccos (\frac{2}{2}) + 2 πn : 2 π - \frac{π}{4} + 2 πn

2 π - arccos (\frac{2}{2}) + 2 πn

Utilizar a seguinte identidade trivial:

arccos (\frac{2}{2}) = \frac{π}{4}

x - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2} 0 \frac{1}{2} \frac{2}{2} \frac{3}{2} 1 arccos (x) π \frac{5 π}{6} \frac{3 π}{4} \frac{2 π}{3} \frac{π}{2} \frac{π}{3} \frac{π}{4} \frac{π}{6} 0 arccos (x) 18 0^{\circ} 15 0^{\circ} 13 5^{\circ} 12 0^{\circ} 9 0^{\circ} 6 0^{\circ} 4 5^{\circ} 3 0^{\circ} 0^{\circ}

= 2 π - \frac{π}{4} + 2 πn

2 x < 2 π - \frac{π}{4} + 2 πn

Dividir ambos os lados por

2

2 x < 2 π - \frac{π}{4} + 2 πn

Dividir ambos os lados por

2

\frac{2 x}{2} < \frac{2 π}{2} - \frac{\frac{π}{4}}{2} + \frac{2 πn}{2}

Simplificar

\frac{2 x}{2} < \frac{2 π}{2} - \frac{\frac{π}{4}}{2} + \frac{2 πn}{2}

Simplificar

\frac{2 x}{2} : x

\frac{2 x}{2}

Dividir:

\frac{2}{2} = 1

= x

Simplificar

\frac{2 π}{2} - \frac{\frac{π}{4}}{2} + \frac{2 πn}{2} : π - \frac{π}{8} + πn

\frac{2 π}{2} - \frac{\frac{π}{4}}{2} + \frac{2 πn}{2}

\frac{2 π}{2} = π

\frac{2 π}{2}

Dividir:

\frac{2}{2} = 1

= π

\frac{\frac{π}{4}}{2} = \frac{π}{8}

\frac{\frac{π}{4}}{2}

Aplicar as propriedades das frações:

\frac{\frac{b}{c}}{a} = \frac{b}{c \cdot a}

= \frac{π}{4 \cdot 2}

Multiplicar os números:

4 \cdot 2 = 8

= \frac{π}{8}

\frac{2 πn}{2} = πn

\frac{2 πn}{2}

Dividir:

\frac{2}{2} = 1

= πn

= π - \frac{π}{8} + πn

x < π - \frac{π}{8} + πn

x < π - \frac{π}{8} + πn

Simplificar

π - \frac{π}{8} : \frac{7 π}{8}

π - \frac{π}{8}

Converter para fração:

π = \frac{π 8}{8}

= \frac{π 8}{8} - \frac{π}{8}

Já que os denominadores são iguais, combinar as frações:

\frac{a}{c} \pm \frac{b}{c} = \frac{a \pm b}{c}

= \frac{π 8 - π}{8}

Somar elementos similares:

8 π - π = 7 π

= \frac{7 π}{8}

x < \frac{7 π}{8} + πn

x < \frac{7 π}{8} + πn

Combinar os intervalos

x > \frac{π}{8} + πn and x < \frac{7 π}{8} + πn

Junte intervalos que se sobrepoem

\frac{π}{8} + πn < x < \frac{7 π}{8} + πn

Exemplos populares

tan(x)<-1.5

tan (x) < - 1.5

-sin(x)<= 0.9

- sin (x) \leq 0.9

cos(θ)<= 1

cos (θ) \leq 1

sin(x)<cos(2x)

sin (x) < cos (2 x)

cos^2(x)+sin(x)+1>= 0

cos^{2} (x) + sin (x) + 1 \geq 0