wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

If f:RR and g:R are defined by f(x)=2x+3 and g(x)=x2+7, then the values of x such that g(f(x))=8 are


A

1, 2

No worries! We‘ve got your back. Try BYJU‘S free classes today!
B

-1, 2

No worries! We‘ve got your back. Try BYJU‘S free classes today!
C

-1, -2

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D

1, -2

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C

-1, -2


f(x)=2x+3 and g(x)=x2+7
g(f(x))=8f(x)22+7=8(2x+3)2+7=84x2+9+12x+7=84x2+12x+16=8x2+3x+4=2x2+3x+2=0(x+2)(x+1)=0x=1,2


flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Composite Functions
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon