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Let f(y)=70+a(2^ky) with f(0)=80   and     f(1)=150

 

 

Find value of a and k and then evaulate the function f(2)

 

stuck on this for 30 minutes someone please give the answer :( thanks so much

 

 

value of a=

 

value of k=

 

f(2)=

 Mar 27, 2020
 #1
avatar+111330 
+2

I'm assuming that this is   ⇒ f(y) =  70 + a(2)^(ky)

 

f(0)   = 80  implies  that

 

80  =  70  + a(2)^(k*0)       

 

80  = 70  + a(2)^(0)

 

80  = 70  + a(1)

 

80  =  70  + 10           a  =10

 

 

f(1)  =150

 

Which implies that

 

150  = 70 + 10 *(2)^(k* 1)     subtract 70 from both sides

 

80  = 10 * (2)^(k)       divide both sides  by  10

 

8  = 2^(k)

 

Note  that  since   2^3  = 8       then      ⇒   k =  3

 

 

f(2)  =  70  + 10 (2)^[ 3 * 2]

 

f(2)  =  70  +  10(2)^6

 

f(2)  =  70 + 10*64

 

f(2)  = 70  + 640

 

f(2)  =  710

 

 

cool cool cool

 Mar 27, 2020

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