What is the value of 3sin(45)+4cos(45) ?

The value of 3sin(45)+4cos(45) is (7sqrt(2))/2

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3sin(45)+4cos(45)

3 sin (4 5^{\circ}) + 4 cos (4 5^{\circ})

\frac{7 2}{2}

Decimal Notation

4.94974 \dots

Solution steps

3 sin (4 5^{\circ}) + 4 cos (4 5^{\circ})

Use the following trivial identity:

sin (4 5^{\circ}) = \frac{2}{2}

sin (4 5^{\circ})

sin (x)

periodicity table with

36 0^{\circ} n

cycle:

x 0 3 0^{\circ} 4 5^{\circ} 6 0^{\circ} 9 0^{\circ} 12 0^{\circ} 13 5^{\circ} 15 0^{\circ} sin (x) 0 \frac{1}{2} \frac{2}{2} \frac{3}{2} 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} x 18 0^{\circ} 21 0^{\circ} 22 5^{\circ} 24 0^{\circ} 27 0^{\circ} 30 0^{\circ} 31 5^{\circ} 33 0^{\circ} sin (x) 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2}

= \frac{2}{2}

Use the following trivial identity:

cos (4 5^{\circ}) = \frac{2}{2}

cos (4 5^{\circ})

cos (x)

periodicity table with

36 0^{\circ} n

cycle:

x 0 3 0^{\circ} 4 5^{\circ} 6 0^{\circ} 9 0^{\circ} 12 0^{\circ} 13 5^{\circ} 15 0^{\circ} cos (x) 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} x 18 0^{\circ} 21 0^{\circ} 22 5^{\circ} 24 0^{\circ} 27 0^{\circ} 30 0^{\circ} 31 5^{\circ} 33 0^{\circ} 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}

= 3 \cdot \frac{2}{2} + 4 \cdot \frac{2}{2}

Simplify

3 \cdot \frac{2}{2} + 4 \cdot \frac{2}{2} : \frac{7 2}{2}

3 \cdot \frac{2}{2} + 4 \cdot \frac{2}{2}

Add similar elements:

3 \cdot \frac{2}{2} + 4 \cdot \frac{2}{2} = 7 \cdot \frac{2}{2}

= 7 \cdot \frac{2}{2}

Multiply fractions:

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

= \frac{2 \cdot 7}{2}

Apply radical rule:

2 = 2^{\frac{1}{2}}

= \frac{7 \cdot 2 ^{\frac{1}{2}}}{2}

Apply exponent rule:

\frac{x ^{a}}{x ^{b}} = \frac{1}{x ^{b - a}}

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

= \frac{7}{2 ^{1 - \frac{1}{2}}}

Subtract the numbers:

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

= \frac{7}{2 ^{\frac{1}{2}}}

Apply radical rule:

2^{\frac{1}{2}} = 2

= \frac{7}{2}

Rationalize

\frac{7}{2} : \frac{7 2}{2}

\frac{7}{2}

Multiply by the conjugate

\frac{2}{2}

= \frac{7 2}{2 2}

22 = 2

22

Apply radical rule:

a a = a

22 = 2

= 2

= \frac{7 2}{2}

= \frac{7 2}{2}

= \frac{7 2}{2}

sinh (0.5)

sec (0.8)

csc (3 0^{\circ}) + tan (4 5^{\circ})

cos (\frac{π}{6}) cos (\frac{π}{4}) - sin (\frac{π}{6}) sin (\frac{π}{4})

sin^{2} (36 0^{\circ})

What is the value of 3sin(45)+4cos(45) ?
The value of 3sin(45)+4cos(45) is (7sqrt(2))/2