Answer:
Part a) Option d
Part b) Option a
Step-by-step explanation:
Part a
if we look at the options given and the data available
Option a) x^4+9
Putting x= 2 we get (2^4) + 9 =25
Putting x= 3 we get (3^4) + 9 =90 but f(x) =125 so not correct option
Option b) (4^x)+9
Putting x= 2 we get (4^2) + 9 =25
Putting x= 3 we get (4^3) + 9 =73 but f(x) =125 so not correct option
Option c) x^5
Putting x= 2 we get (2^5) =32 but f(x) =25 so not correct option
Option d) 5^x
Putting x= 2 we get (5^2) =25
Putting x= 3 we get (5^3) =125
Putting x= 4 we get (5^4) =625
So Option d is correct.
Part (b)
3(2)^3x
can be solved as:
=3(2^3)^x
=3(8)^x
So, correct option is a
<span>
6 Find an exact value. sin 75°
</span>sin(A+B)=sin(A)cos(B)+cos(A)sin<span>(B)
</span>sin(45)=cos(45)=(2^0.5)/2 sin(30)=0.5 cos(30)=(3^0.5)/2
sin(45+30)=sin(45)cos(30)+cos(45)sin(30)=(6^0.5+2^0.5)/4
the answer is the letter d) quantity square root of six plus square root of two divided by four.
<span>
7. Find an exact value. sine of negative eleven pi divided by twelve.
</span>sin(-11pi/12) = -sin(11pi/12) = -sin(pi - pi/12) = -sin(pi/12) = -sin( (pi/6) / 2)
= - sqrt( (1-cos(pi/6) ) / 2) = -sqrt( (1-√3/2) / 2 ) = -(√3-1) / 2√2=(√2-√6)/4
the answer is the letter c) quantity square root of two minus square root of six divided by four.
<span>
8. Write the expression as the sine, cosine, or tangent of an angle. sin 9x cos x - cos 9x sin x
</span>
sin(A−B)=sinAcosB−cosAsinB
sin(9x−x)= sin9xcosx−cos9xsinx= sin(8x)
the answer is the letter c) sin 8x
<span>
9. Write the expression as the sine, cosine, or tangent of an angle. cos 112° cos 45° + sin 112° sin 45°</span>
cos(A−B)=cosAcosB<span>+sinA</span>sinB
cos(112−45)=cos112cos45<span>+sin112</span>sin45=cos(67)
the answer is the letter d) cos 67°
10. Rewrite with only sin x and cos x.
sin 2x - cos 2x
sin2x =
2sinxcosx<span>
cos2x = (cosx)^2 - (sinx)^2 = 2(cosx)^2 -1 = 1- 2(sinx)^2</span>
sin2x- cos2x=2sinxcosx-(1- 2(sinx)^2=2sinxcosx-1+2(sinx)^2
sin2x- cos2x=2sinxcosx-1+2(sinx)^2
<span>
the answer is the letter <span>
b) 2 sin x cos2x - 1
+ 2 sin2x</span></span>
Answer:
Step-by-step explanation:
we're asked to solve the equation two x squared plus three is equal to 75 so in this situation it looks like we might be able to isolate the x squared pretty simply because there's only one term that involves the next year it's only this x squared term so let's try to do that so let me just rewrite it we have two x squared plus three is equal to 75 I'm going to try to isolate this x squared ...
Solve this equation: $45 - ($2.75/pen)x = $12. Simplifying, we get
$33 = ($2.75)x, so that
x = $33 / ($2.75) = 12.
Tim's buying 12 pens leaves him with $12.
Answer:
I think its c
Step-by-step explanation:
