Seudónimo Seudónimo
  • 04-05-2017
  • Mathematics
contestada


The function f is defined by f(x)=x^2+3x-10 If f(x+5)=x^2+kx+30, k= Find the smallest zero of f(x+5), x=

Respuesta :

Аноним Аноним
  • 04-05-2017
f(x+5)
Step1:
f(x+5)=(x+5)^2+3(x+5)-10
f(x+5)=x^2+10x+25+3x+15-10
f(x+5)=x^2+13x+30

Step
f(x)=x^2+3x-10
f(x+5)=x^2+13x+30


f(x+5)=0

0=x^2+13x+30
factor
0=(x+3)(x+10)


x+3=0
x=-3

x+10=0
x=-10

-10<-3

smalle zero is x=-10.....
Answer Link
irspow
irspow irspow
  • 04-05-2017
f(x+5)=(x+5)^2+3(x+5)-10

f(x+5)=x^2+10x+25+3x+15-10

f(x+5)=x^2+13x+30  and f(x+5)=x^2+kx+30 so

k=13

Now factor x^2+13x+30

Find j and k such that jk=ac=30 and j+k+b=13 so j and k are 10 and 3 so

(x+3)(x+10)

So the two zeros occur when x=-3 and -10 the smallest of which is:

x=-10


Answer Link

Otras preguntas

what other areas beside egypt did the new kingdom pharoahs conquer
If you are writing a persuasive essay in favor of banning vending machines in schools, which is a counterargument you might anticipate?
what other areas beside egypt did the new kingdom pharoahs conquer
If you are writing a persuasive essay in favor of banning vending machines in schools, which is a counterargument you might anticipate?
write words to match the expression. 24- ( 6+3)
what other areas beside egypt did the new kingdom pharoahs conquer
what other areas beside egypt did the new kingdom pharoahs conquer
write words to match the expression. 24- ( 6+3)
write words to match the expression. 24- ( 6+3)
If you are writing a persuasive essay in favor of banning vending machines in schools, which is a counterargument you might anticipate?