Hi
We need to solve
⁴√81 - 8 ³√216 + 15 5√32 + √225
Lets write every term separately
- 81 = 3 × 3 × 3 × 3 = 34
- 216 = 6 × 6 × 6 = 63
- 32 = 2 × 2 × 2 × 2 × 2 = 25
- 225 = 15 × 15 = 152
Now, our equation becomes
⁴√81 - 8 ³√216 + 15 5√32 + √225
= ⁴√34 - 8 ³√63 + 15 5√25 + √152
All the roots cancel out
= 3 - 8 × 6 + 15 × 2 + 15
= 3 - 48 + 30 + 15
= 3 + 30 + 15 - 48
= 48 - 48
= 0
Written on Oct. 22, 2017, 8:20 p.m.