Normal 0 false false false EN-US JA AR-SA MicrosoftInternetExplorer4 I have a problem to write a expression on the band math for create vegetation index to analysis my data. I have been trying to create a index, but I can not exactly writing equation. Each time I try that this massage appear ‘’ You have entered an invalid expression. Check for syntax errors or undefined procedures and functions and try again.’’ Normal 0 false false false EN-US JA AR-SA MicrosoftInternetExplorer4 For example I want to write this index but in the result I showed in  the display and I check data values not right. This index; MSAVI2: second Modified Soil Adjusted Vegetation Index MSAVI2 = (1/2)*(2(NIR+1)-sqrt((2*NIR+1)^2-8(NIR-red))). Must be data range from -1 to +1 Normal 0 false false false EN-US JA AR-SA MicrosoftInternetExplorer4 for this index. Could you help me. Thank you