All categories

2 years ago

Please help! Will mark brainliest

Mathematics

1 answer:

ser-zykov [4K]2 years ago

5 0

Answer:

Step-by-step explanation:

t1 = a1

t2 = a1 + d

t3 = a1 + 2d

The sum is t1 + t2 + t3 = a1 + a1 + d + a1 + 2d = 3a1 + 3d

Second question

t1 = a1

t2 = a1 + d

t3 = a1 + 2d

t4 = a1 + 3d

...

tn = a1 + (n - 1)*d

Sum = (a1 + a1 + (n- 1)*d) * n / 2

Sum = (2a1 + nd - d) * n / 2

Sum = (2a1*n + n^2*d - nd) / 2

You might be interested in

In Mrs. Robinson's class, there are 16 girls and 14 boys. The mean of the girls' heights is 63.7 inches, and the mean of the boy

Elodia [21]

Answer: 64.6

Step-by-step explanation:

If you add up 63.7 and 65.4 and then divide by 2 you get 64.6.

8 0

2 years ago

Verify each trigonometric equation by substituting identities to match the right hand side of the equation to the left hand side

lorasvet [3.4K]

Answer:

Step-by-step explanation:

cot x sec⁴ x = cot x+2 tan x +tan³x

L.H.S = cot x sec⁴x

=cot x (sec²x)²

=cot x (1+tan²x)² [ ∵ sec²x=1+tan²x]

= cot x(1+ 2 tan²x +tan⁴x)

=cot x+ 2 cot x tan²x+cot x tan⁴x

=cot x +2 tan x + tan³x [ ∵cot x tan x $=\frac{ \textrm{tan x }}{\textrm{tan x}}$ =1]

=R.H.S

(sin x)(tan x cos x - cot x cos x)=1-2 cos²x

L.H.S =(sin x)(tan x cos x - cot x cos x)

= sin x tan x cos x - sin x cot x cos x

$=\textrm{sin x cos x }\times\frac{\textrm{sin x}}{\textrm{cos x} } - \textrm{sinx}\times\frac{\textrm{cos x}}{\textrm{sin x}}\times \textrm{cos x}$

= sin²x -cos²x

=1-cos²x-cos²x

=1-2 cos²x

=R.H.S

1+ sec²x sin²x =sec²x

L.H.S =1+ sec²x sin²x

= $1+\frac{{sin^2x}}{cos^2x}$ [ $\textrm{sec x}=\frac{1}{\textrm{cos x}}$ ]

=1+tan²x $[\frac{\textrm{sin x}}{\textrm{cos x}} = \textrm{tan x}]$

=sec²x

=R.H.S

$\frac{\textrm{sinx}}{\textrm{1-cos x}} +\frac{\textrm{sinx}}{\textrm{1+cos x}} = \textrm{2 csc x}$

L.H.S= $\frac{\textrm{sinx}}{\textrm{1-cos x}} +\frac{\textrm{sinx}}{\textrm{1+cos x}}$

$=\frac{\textrm{sinx(1+cos x)+{\textrm{sinx(1-cos x)}}}}{\textrm{(1-cos x)\textrm{(1+cos x})}}$

$=\frac{\textrm{sinx+sin xcos x+{\textrm{sinx-sin xcos x}}}}{{(1-cos ^2x)}}$

$=\frac{\textrm{2sin x}}{sin^2 x}$

= 2 csc x

= R.H.S

-tan²x + sec²x=1

L.H.S=-tan²x + sec²x

= sec²x-tan²x

= $\frac{1}{cos^2x} -\frac{sin^2x}{cos^2x}$

$=\frac{1- sin^2x}{cos^2x}$

$=\frac{cos^2x}{cos^2x}$

8 0

3 years ago

There are 16 marbles in a bag 12 of them are blue and 4 are yellow. what is the probability of picking a blue marble then a yell

Art [367]

Answer:

1/5

Step-by-step explanation:

the prob that you will pick a blue marble would be 12/16, easy.

then the prob of picking a yellow marble after that would be 4/15 since one marble is already missing. multiply the numerator and denominator of each fraction. so 12 x 4 and 16 x 15 to get 48/240. then divide each by 48 to get 1/5.

3 0

2 years ago

Pls help I’ll give brainliest

DanielleElmas [232]

Answer:

B) 7 gallons

Step-by-step explanation:

car begins with 12 gallons and, at a rate of 29 mpg, would allow the car to travel for 348 miles

car only traveled 140 miles so 208 miles more can be driven

208÷29 is approx 7 gallons

7 0

2 years ago

Ms. Joseph wants to take her mother to see the Color Purple. Tickets in the mezzanine cost $140

ValentinkaMS [17]

Answer:

223.56$

The ans is simple

Add all the given values

Then we get the ans

Step-by-step explanation:

The ans is simple

Add all the given values

Then we get the ans

8 0

2 years ago