What is the value of 128+127.5sin((2pi)/(16)*9) ?

The value of 128+127.5sin((2pi)/(16)*9) is (512-255sqrt(2-\sqrt{2)})/4

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

128+127.5sin((2pi)/(16)*9)

Solution

128 + 127.5 sin (\frac{2 π}{16} \cdot 9)

Solution

\frac{512 - 255 2 - 2}{4}

Decimal Notation

79.20786 \dots

Solution steps

128 + 127.5 sin (\frac{2 π}{16} \cdot 9)

= 128 + \frac{255}{2} sin (\frac{2 π}{16} \cdot 9)

Simplify:

\frac{2 π}{16} \cdot 9 = \frac{9 π}{8}

\frac{2 π}{16} \cdot 9

Multiply fractions:

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

= \frac{2 π 9}{16}

Multiply the numbers:

2 \cdot 9 = 18

= \frac{18 π}{16}

Cancel the common factor:

2

= \frac{9 π}{8}

128 + \frac{255}{2} sin (\frac{9 π}{8}) = \frac{256 + 255 sin ( \frac{9 π}{8} )}{2}

128 + \frac{255}{2} sin (\frac{9 π}{8})

Multiply

\frac{255}{2} sin (\frac{9 π}{8}) : \frac{255 sin ( \frac{9 π}{8} )}{2}

\frac{255}{2} sin (\frac{9 π}{8})

Multiply fractions:

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

= \frac{255 sin ( \frac{9 π}{8} )}{2}

= 128 + \frac{255 sin ( \frac{9 π}{8} )}{2}

Convert element to fraction:

128 = \frac{128 \cdot 2}{2}

= \frac{128 \cdot 2}{2} + \frac{255 sin ( \frac{9 π}{8} )}{2}

Since the denominators are equal, combine the fractions:

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

= \frac{128 \cdot 2 + 255 sin ( \frac{9 π}{8} )}{2}

Multiply the numbers:

128 \cdot 2 = 256

= \frac{256 + 255 sin ( \frac{9 π}{8} )}{2}

= \frac{256 + 255 sin ( \frac{9 π}{8} )}{2}

Rewrite using trig identities:

sin (\frac{9 π}{8}) = - \frac{2 - 2}{2}

sin (\frac{9 π}{8})

Rewrite using trig identities:

- \frac{1 - cos ( \frac{π}{4} )}{2}

sin (\frac{9 π}{8})

Write

sin (\frac{9 π}{8})

sin (\frac{\frac{9 π}{4}}{2})

= sin (\frac{\frac{9 π}{4}}{2})

Use the Half Angle identity:

sin (\frac{θ}{2}) = - \frac{1 - cos ( θ )}{2}

Use the Double Angle identity

cos (2 θ) = 1 - 2 sin^{2} (θ)

Substitute

θ

with

\frac{θ}{2}

cos (θ) = 1 - 2 sin^{2} (\frac{θ}{2})

Switch sides

2 sin^{2} (\frac{θ}{2}) = 1 - cos (θ)

Divide both sides by

2

sin^{2} (\frac{θ}{2}) = \frac{( 1 - cos ( θ ) )}{2}

Square root both sides

Choose the root sign according to the quadrant of

\frac{θ}{2}

range [0, \frac{π}{2}] [\frac{π}{2}, π] [π, \frac{3 π}{2}] [\frac{3 π}{2}, 2 π] quadrant I II III I V sin positive positive negative negative cos positive negative negative positive

sin (\frac{θ}{2}) = - \frac{( 1 - cos ( θ ) )}{2}

= - \frac{1 - cos ( \frac{9 π}{4} )}{2}

cos (\frac{9 π}{4}) = cos (\frac{π}{4})

cos (\frac{9 π}{4})

Rewrite

\frac{9 π}{4}

2 π + \frac{π}{4}

= cos (2 π + \frac{π}{4})

Apply the periodicity of

cos

cos (x + 2 π) = cos (x)

cos (2 π + \frac{π}{4}) = cos (\frac{π}{4})

= cos (\frac{π}{4})

= - \frac{1 - cos ( \frac{π}{4} )}{2}

= - \frac{1 - cos ( \frac{π}{4} )}{2}

Use the following trivial identity:

cos (\frac{π}{4}) = \frac{2}{2}

cos (\frac{π}{4})

cos (x)

periodicity table with

2 πn

cycle:

x 0 \frac{π}{6} \frac{π}{4} \frac{π}{3} \frac{π}{2} \frac{2 π}{3} \frac{3 π}{4} \frac{5 π}{6} cos (x) 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} x π \frac{7 π}{6} \frac{5 π}{4} \frac{4 π}{3} \frac{3 π}{2} \frac{5 π}{3} \frac{7 π}{4} \frac{11 π}{6} cos (x) - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2} 0 \frac{1}{2} \frac{2}{2} \frac{3}{2}

= \frac{2}{2}

= - \frac{1 - \frac{2}{2}}{2}

Simplify

- \frac{1 - \frac{2}{2}}{2} : - \frac{2 - 2}{2}

- \frac{1 - \frac{2}{2}}{2}

\frac{1 - \frac{2}{2}}{2} = \frac{2 - 2}{4}

\frac{1 - \frac{2}{2}}{2}

Join

1 - \frac{2}{2} : \frac{2 - 2}{2}

1 - \frac{2}{2}

Convert element to fraction:

1 = \frac{1 \cdot 2}{2}

= \frac{1 \cdot 2}{2} - \frac{2}{2}

Since the denominators are equal, combine the fractions:

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

= \frac{1 \cdot 2 - 2}{2}

Multiply the numbers:

1 \cdot 2 = 2

= \frac{2 - 2}{2}

= \frac{\frac{2 - 2}{2}}{2}

Apply the fraction rule:

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

= \frac{2 - 2}{2 \cdot 2}

Multiply the numbers:

2 \cdot 2 = 4

= \frac{2 - 2}{4}

= - \frac{2 - 2}{4}

Simplify

\frac{2 - 2}{4} : \frac{2 - 2}{2}

\frac{2 - 2}{4}

Apply radical rule:

assuming

a \geq 0, b \geq 0

= \frac{2 - 2}{4}

4 = 2

4

Factor the number:

4 = 2^{2}

= 2^{2}

Apply radical rule:

2^{2} = 2

= 2

= \frac{2 - 2}{2}

= - \frac{2 - 2}{2}

= - \frac{2 - 2}{2}

= \frac{256 + 255 ( - \frac{2 - 2}{2} )}{2}

Simplify

\frac{256 + 255 ( - \frac{2 - 2}{2} )}{2} : \frac{512 - 255 2 - 2}{4}

\frac{256 + 255 ( - \frac{2 - 2}{2} )}{2}

Remove parentheses:

(- a) = - a

= \frac{256 - 255 \cdot \frac{2 - 2}{2}}{2}

Multiply

255 \cdot \frac{2 - 2}{2} : \frac{255 2 - 2}{2}

255 \cdot \frac{2 - 2}{2}

Multiply fractions:

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

= \frac{2 - 2 \cdot 255}{2}

= \frac{256 - \frac{255 2 - 2}{2}}{2}

Join

256 - \frac{2 - 2 \cdot 255}{2} : \frac{512 - 255 2 - 2}{2}

256 - \frac{2 - 2 \cdot 255}{2}

Convert element to fraction:

256 = \frac{256 \cdot 2}{2}

= \frac{256 \cdot 2}{2} - \frac{2 - 2 \cdot 255}{2}

Since the denominators are equal, combine the fractions:

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

= \frac{256 \cdot 2 - 2 - 2 \cdot 255}{2}

Multiply the numbers:

256 \cdot 2 = 512

= \frac{512 - 255 2 - 2}{2}

= \frac{\frac{512 - 255 2 - 2}{2}}{2}

Apply the fraction rule:

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

= \frac{512 - 2 - 2 \cdot 255}{2 \cdot 2}

Multiply the numbers:

2 \cdot 2 = 4

= \frac{512 - 255 2 - 2}{4}

= \frac{512 - 255 2 - 2}{4}

Popular Examples

128+127.5sin((2pi)/(16)*8)

128 + 127.5 sin (\frac{2 π}{16} \cdot 8)

15sin(10)

15 sin (1 0^{\circ})

128+127.5sin((2pi)/(16)*2)

128 + 127.5 sin (\frac{2 π}{16} \cdot 2)

128+127.5sin((2pi)/(16)*5)

128 + 127.5 sin (\frac{2 π}{16} \cdot 5)

128+127.5sin((2pi)/(16)*6)

128 + 127.5 sin (\frac{2 π}{16} \cdot 6)

Frequently Asked Questions (FAQ)

What is the value of 128+127.5sin((2pi)/(16)*9) ?
The value of 128+127.5sin((2pi)/(16)*9) is (512-255sqrt(2-\sqrt{2)})/4