All categories

3 years ago

.prove that cos (90-A).sinA + sin(90 - A).cosA = 1

Mathematics

1 answer:

pav-90 [236]3 years ago

4 0

Answer:

See Explanation

Step-by-step explanation:

$cos (90-A).sinA + sin(90 - A).cosA = 1 \\ \\ LHS = cos (90-A).sinA + sin(90 - A).cosA \\ \\ = sinA.sinA + cosA.cosA\\ \\ = sin ^{2} A + cos^{2} A \\ \\ = 1 \\ \\=RHS\\\\ reason \\ cos (90- \theta) = sin \theta \\ sin (90- \theta) = cos \theta \\ sin ^{2} \theta + cos^{2} \theta = 1 \\ \\ thus \: proved \\$

You might be interested in

I was at the store, and saw two sizes of avocados being sold. The smaller size sold for $0.92 each. For what prices would the la

Firdavs [7]

Answer:

Large avocados should cost $ 1.83 or less to be a good deal.

Step-by-step explanation:

Since there are two types of avocado in the store, some small at $ 0.92 and others larger, to determine at what price large avocados would be a good deal, an equivalence must be established in this regard:

Thus, if two small avocados are equal to one large, buying two small avocados at $ 0.92 the total price would be $ 1.84. Therefore, any large avocado that sells for less than $ 1.84 would be a good deal. Thus, large avocados should cost $ 1.83 or less to be a good deal.

3 0

3 years ago

3x3-27x=0<br> Solve by factoring a

Eddi Din [679]

After factoring $3x^3-27x=0$ the solutions are x=0 , x=3, x= -3

Step-by-step explanation:

We need to solve by factoring:

$3x^3-27x=0$

Solving:

$3x^3-27x=0$

Taking 3x common:

$3x(x^2-9)=0$

Now using formula $a^2-b^2=(a-b)(a+b)$

$3x((x)^2-(3)^2)=0\\3x(x-3)(x+3)=0$

$3x=0\,\,and\,\,x+3=0\,\,and\,\,x-3=0\\x=0\,\,and\,\,x=-3\,\,and\,\,x=3\\$

So, After factoring $3x^3-27x=0$ the solutions are x=0 , x=3, x= -3

Keywords: Factorization

Learn more about Factorization at:

#learnwithBrainly

5 0

3 years ago

HELP!!! What is the slant height x of the square pyramid? Express your answer in radical form.

katrin [286]

Check the picture below.

make sure your calculator is in Degree mode.

3 0

3 years ago

A bowl is the shape of a hemisphere and made out of thick clay. The diameter of the outside bowl is 44.6 cm. And the diameter of

aleksandr82 [10.1K]

Answer:

Step-by-step explanation:

Ive already explained this somebody else asked if you find it you will have the answer

3 0

3 years ago

What is the shape of the cross-section formed when a plane containing line AC and line EH intersects this cube? What is the area

velikii [3]

Answer:

Cross section is a rectangle.

Area of cross section = 16 sqrt(2) = 22.63 sq. units (to 2 decimals)

Step-by-step explanation:

Given a cube.

top face ABCD is parallel and congruent to bottom face EFGH ........(1)

justified by the properties of cubes

Sides AE and CH are perpendicular to faces ABCD and EFGH ..........(2)

justified by the properties of cubes

Diagonals AC and EH are congruent ......................(3)

justified by (1), congruent top and bottom faces

Consider cross-section ACHE

AC is congruent and parallel to EH (1) & (3)

EA & HC are perpendicular to AC (2)

Therefore the quadrilateral ACHE is a rectangle.

Length of diagonal AC = sqrt(4^2+4^2) = 4 sqrt(2) ..........pythagoras theorem

AE = CH = DG = 4 properties of cube, all sides equal

Area of ACHE = 4* 4sqrt(2) = 16 sqrt(2) = 22.63 sq. units

4 0

3 years ago

.prove that cos (90-A).sinA + sin(90 - A).cosA = 1 ​

.prove that cos (90-A).sinA + sin(90 - A).cosA = 1